Role players serve as key cogs to any team's success, even if their contributions go unnoticed. 

Being described as a cog is often construed as a negative when the opposite is true. Every business model requires those to consistently produce.  

The NFL is no different, and an accepted hierarchy exists in every locker room. Not every individual can be a superstar even though all players strive to become one. 

Unsung performers form the roster's backbone. They don't receive Pro Bowl or All-Pro recognition. They're not rookies whose potential often creates a certain fervor. Others on the squad tend to overshadow their accomplishments as well. 

Yet, they're invaluable pieces. 

The following aren't considered among the elite, yet their successes or failures serve as a crux to their team's 2018 performance. 

Arizona Cardinals: DT Olsen Pierre

While everyone continues to wait for 2016 first-round pick Robert Nkemdiche to emerge, Olsen Pierre will quietly go about his job as a quality 3-technique. 

Pierre may have gone undrafted in 2015, but he's shown far more than Nkemdiche and finds himself in an ideal situation in the transition from the Cardinals' previous 3-4 look into head coach Steve Wilks' four-man front. 

"When you're in a 3-4, you have to do so many exotic looks to get to the quarterback, versus with a 4-3, it's just gap assignment," Pro Bowl cornerback and defensive captain Patrick Peterson said, per Jess Root of USA Today's Cardinals Wire. "Guys just line up and play football versus being a two-gap reader."

Pierre's game is predicated on first-step quickness and penetration. Last season, the interior defender finished second on the squad with 5.5 sacks.

The ability to collapse the pocket is crucial when a team features the league's leading sack artist—Chandler Jones (17.0) in this case. A quarterback's inability to step up in the pocket due to pressure provides edge-rushers with more opportunities. 

Atlanta Falcons: LB De'Vondre Campbell

Atlanta Falcons linebacker De'Vondre Campbell isn't shy about discussing how good he is. 

"Stop comparing me to people, bruh. I had a better year than [Anthony] Barr last year," Campbell tweeted when a fan compared him to the three-time Pro Bowl selection. 

He's right. Campbell posted more total tackles (92-75) and sacks (2-1) last year than Barr, who the Vikings selected with the ninth pick in the 2014 draft and is expected to become a top free agent next offseason. 

Yet, the third-year linebacker doesn't often receive his due as a 2016 fourth-round pick in a defense that already features Vic Beasley, Grady Jarrett, Deion Jones, Keanu Neal and Desmond Trufant. It's a young, talented unit in which Campbell plays a nonessential position at strong-side linebacker. 

But the 25-year-old provides value with his versatility. Campbell is athletic enough to cover tight ends and has the size and length (6'3", 234 lbs) to contribute in sub-packages as an edge-rusher. This flexibility allows the linebacker to stay on the field when others at this position tend to be part-timers. 

Baltimore Ravens: CB Tavon Young

Tavon Young looked well on his way to becoming one of the league's best young cornerbacks after a stellar rookie year only to suffer a season-ending ACL tear during organized teams activities in 2017. 

Young established himself as a crucial part of the Baltimore Ravens secondary upon his return. 

"Tavon is coming right back to where he was," secondary coach Chris Hewitt said last month, per the team's official site. "He's getting his quickness back. One thing about Tavon is he has always been a top competitor." 

The third-year player solidified himself as the defense's nickel corner during training camp.  

"He does a great job of contesting passes in the end," head coach John Harbaugh said, per the Baltimore Sun's Edward Lee. "There's a lot that goes into that. He's a good tackler; he's a good blitzer. He stays close to receivers for a lot of different reasons and contests passes really well. That's the essence of the position."

Jimmy Smith's four-game suspension for a violation of the NFL's personal conduct policy makes Young's return to the lineup even more crucial.

Buffalo Bills: LT Dion Dawkins

Dion Dawkins' rookie performance prompted the Buffalo Bills to trade veteran left tackle Cordy Glenn to the Cincinnati Bengals in March. Dawkins graded as a top-five left tackle after becoming a full-time starter during the final eight games of the 2017 campaign, according to Pro Football Focus. 

"He's going to end up being a Pro Bowler, and I've had a few Pro Bowl players," Bills offensive line coach Juan Castillo said last month, per the Democrat and Chronicle's Sal Maiorana. "He has that kind of ability. The future is bright for him; great kid, works hard, and it's good that every once in a while when he gets beat, everybody [notices] because everybody expects big things for him and I think he's up for the challenge."

The deal allowed the Bills to make a play for the seventh overall pick and select quarterback Josh Allen. Dawkins is vital in keeping the team's quarterbacks upright since the rest of the offensive line is suspect after Eric Wood and Richie Incognito's retirements. 

Carolina Panthers: LT Taylor Moton

Taylor Moton played left tackle for the Western Michigan Broncos before becoming a 2017 second-round selection by the Carolina Panthers. He's back at his natural position. 

The Panthers envisioned Moton as a right tackle until Daryl Williams claimed the spot. The 6'5", 325-pound blocker then opened training camp as the best option to replace Andrew Norwell at left guard. Now, Moton is needed on the blind side after Matt Kalil went on injured reserve in early September after arthroscopic knee surgery. 

"As an offensive lineman who plays a lot of different positions, if you understand the concept of each play instead of just memorizing what you do, it helps out a lot," Moton explained, per ESPN.com's David Newton. "If you understand it like that, it makes the job of understanding the concept a lot easier."

The Panthers may have found the answer at a premium position.  

"To see him be able to flex over to the left side has been very pleasing," head coach Ron Rivera said of Moton. "If you can do that, that's a big deal."

Chicago Bears: TE Trey Burton

Trey Burton will be forever known in Super Bowl lore as the tight end who successfully threw the touchdown pass to Philadelphia Eagles quarterback Nick Foles. 

Now, Burton is in a much better position to contribute as the starting tight end of the Chicago Bears after signing a four-year, $32 million free-agent contract this offseason. 

The Bears' investment in the 26-year-old became overshadowed by the team's other offensive additions, particularly wide receiver Allen Robinson. But Matt Nagy understands the value Burton brings after the head coach's time in Kansas City with Travis Kelce. 

"And when you have a guy that has the size that Trey has and the speed that he has, it's about mismatches," he said, per Fantasy Pros' Nicholas Traicoff. "That's one of the things that I learned through Coach [Andy] Reid is getting mismatches throughout, and that's what Trey does."

Burton and Adam Shaheen were supposed to form a dynamic duo. The team placed Shaheen on injured reserve this week, though, according to Pro Football Talk's Charean Williams. 

Cincinnati Bengals: DT Andrew Billings

Andrew Billings is a classic example of a draft pick who needed time before he could become a consistent contributor. 

"I think he's coming along great," Geno Atkins said, per Cincy Jungle's Josh Kirkendoll. "He's understanding the game a lot better, and the speed is slowing down [for him]."

Billings is 23 years old as he enters his third season and is the projected starter at 1-technique alongside the dominant Atkins.

The 2016 fourth-round pick suffered a season-ending meniscus tear before his rookie campaign and didn't display much consistency in year two. Still, his skill set looks like he could be the perfect nose tackle thanks to his size (6'1", 325 lbs), prodigious natural strength and first-step quickness. Billings' physically overwhelmed blockers during the preseason. 

Interior defenders don't receive much attention unless they can get after the quarterback. But Billings should benefit from playing alongside Atkins, Carlos Dunlap and Carl Lawson. 

Cleveland Browns: CB Terrance Mitchell

The Cleveland Browns placed an emphasis on revamping the secondary this offseason. The front office signed three cornerbacks—T.J. Carrie, E.J. Gaines and Terrance Mitchell—and drafted Denzel Ward with the fourth pick. 

Carrie received the bigger payday, but Mitchell won the starting job. 

"He has been outstanding," head coach Hue Jackson said of the 26-year-old defensive back, per the Associated Press' Brian Dulik. "He is competitive. He went and grabbed hold of that position because of the way he performed in training camp, and he has shown that in the games."

Defensive coordinator Gregg Williams system requires aggressive corners to utilize more man-press coverage. According to Pro Football Focus, Mitchell graded as the third-best cornerback through three preseason games before most teams sat their starters. 

Plenty is already expected of Ward as a top draft pick. Mitchell, on the other hand, went from the team's third or fourth cornerback option to becoming the rookie's bookend and a full-time starter for the first time. 

Dallas Cowboys: C Joe Looney

Travis Frederick's return date after being diagnosed with Guillain-Barre syndrome has yet to be determined. The Dallas Cowboys decided not to place the game's best center on short-term injured reserve, according to the Star-Telegram's Clarence E. Hill Jr.

As a result, backup Joe Looney becomes the team's X-factor as he tries to stabilize the game's most talented offensive front without its four-time Pro Bowl snapper. 

"Joe's been in the league, I mean, shoot, this is his sixth or seventh year," Pro Bowl right guard Zack Martin said, per ESPN.com's Todd Archer. "He's played a lot of football, been in our system for three years now, so we're very, very comfortable and confident in what he brings to us."

Looney, a 2012 fourth-round pick by the San Francisco 49ers, has 13 career starts, including three for the Cowboys in 2016. 

Dallas' offense is built upon a strong foundation. Cracks are starting to show, though. Looney must serve as the sealant until Frederick returns. 

Denver Broncos: CB Bradley Roby

Bradley Roby spent his first four seasons as the Denver Broncos' third cornerback despite his first-round status. He will now start opposite Chris Harris Jr. after the organization traded Aqib Talib to the Los Angeles Rams. 

"He grew up this offseason," Harris said of Roby at the start of training camp, per Aric DiLalla of the Broncos official site. "He kind of took that next step. You all have to kind of take that next step, come into your own. That's what I call it. He came into his own this offseason."

Previously, Roby came in on third downs and played outside corner while Harris slid inside to cover the slot. The 26-year-old cornerback has big shoes to fill after Talib made the Pro Bowl each of the four seasons he played in Denver. Plus, the fifth-year defensive back presents a different skill set as a speedster compared to Talib's physical nature. 

The Broncos finished fourth in pass defense last season, and Roby's maturation will play a big part if the unit expects to maintain that standard.

Detroit Lions: RB Theo Riddick

The Detroit Lions' running game overhaul makes Theo Riddick no less valuable to their backfield rotation. 

Yes, LeGarrette Blount and Kerryon Johnson will receive the majority of reps on early downs, but Riddick is counted among the league's best third-down backs. He's a weapon as a receiver with 186 receptions over the last three seasons. 

The 2013 sixth-round pick led all running backs in yards per route run and made tacklers miss 25.8 percent of the time over the last five years, according to Pro Football Focus. 

As good as Riddick is as a receiver, his understanding of blocking schemes and blitzes improves with each passing season. He's an ideal back to play under new head coach Matt Patricia, who saw the value of James White during his time with the New England Patriots. 

Blount is a bulldozer. Johnson is the slasher. Riddick is the versatile piece to complete the Lions' running back stable. 

Green Bay Packers: LB Blake Martinez

Total tackles tends to be an overrated stat since the NFL's best defenders don't usually finish atop the leaderboard, yet those who do exemplify certain traits most teams desire: consistency, reliability and mental acuity. 

Blake Martinez tied for first overall last season with Preston Brown and Joe Schobert by making 144 total tackles. But his accountability in the middle makes the linebacker an integral part of a Packers defense that features Clay Matthews, Mike Daniels, Ha Ha Clinton-Dix and free-agent addition Muhammad Wilkerson. 

Now in his third season, Martinez is the voice of the defense, especially after Jake Ryan's season-ending knee injury.

The Packers plan to start rookie Oren Burks beside Martinez. Burks is extremely athletic and flies around the field, but it falls on the 24-year-old veteran to communicate with each part of the defense and make sure everyone is lined up correctly. 

"I feel like Blake commands respect of the defense, and he's like in everything, and so when he's out I have to take over that role," Burks said, per the Milwaukee Journal Sentinel's Tom Silverstein. 

Houston Texans: LT Julie'n Davenport

Deshaun Watson's health is the key to the Houston Texans' 2018 campaign. Watson looked like a legitimate MVP candidate for seven games, but the rookie signal-caller took a beating behind a horrible offensive line before suffering a torn ACL in practice.

The organization made the front five a top priority this offseason by signing right tackle Seantrel Henderson and guards Senio Kelemete and Zach Fulton. 

But Julie'n Davenport remains at left tackle after starting four games last season. 

"He played at the end of the year, and he held his own against some pretty good defensive ends," head coach Bill O'Brien told reporters at minicamp. "That was a good beginning for him, and I think he's built on that."

Physically, the second-year blocker is everything a team wants in a blindside protector. He's 6'7" and 320 pounds with 36.5-inch arms and good movement. How his technique develops will determine whether the team has a long-term solution at a premium position. 

Indianapolis Colts: DE Jabaal Sheard

A defensive line's ability to create pressure is critical to a Cover 2-heavy scheme. The Indianapolis Colts aren't loaded with natural pass-rushers to properly execute defensive coordinator Matt Eberflus' game plan.

As such, Jabaal Sheard is making the transition from 3-4 outside linebacker to his more natural defensive end spot. 

"I think Jabaal Sheard is an ideal fit," general manager Chris Ballard said before training camp, per Jake Arthur of the Colts official site. "I think Jabaal Sheard will take off in this defense. Jabaal is a good football player."

The 29-year-old Sheard has played in a four-man front before, but he's never eclipsed 8.5 sacks in any season. The Colts need more from the experienced edge-rusher, though.  

Indianapolis' defense lacks playmakers, especially those who can consistently create pressure. The team's investments in the second and third levels won't mean much if the defensive line is overwhelmed. As such, Sheard must develop into the point man for the entire unit.  

Jacksonville Jaguars: RB Corey Grant

The Jacksonville Jaguars are loaded at running back with Leonard Fournette and T.J. Yeldon. But It says something when a coaching staff believes it has to get another back on the field, and Corey Grant is forcing the staff's hand. 

"He's a guy that stepped in and did a great job there at the end," offensive coordinator Nathaniel Hackett told reporters, "and he's just a guy we've got to get out there. ... I'd love to put him out there because he's a major change-of-pace back. He's a guy that can catch the ball from the backfield. And even every time we've given him the ball in the backfield, he's done really good things."

Grant is more explosive than Fournette and Yeldon. The 203-pound back from Auburn ran a 4.28-second 40-yard dash at his pro day. 

When Jaguars opponents have to face the pounding that Fournette unleashes, Grant is the ideal changeup. Defenses will struggle to adjust. An expanded role for the fourth-year back should make last year's top-ranked rushing offense even more potent. 

Kansas City Chiefs: CB Kendall Fuller

So much relies on Patrick Mahomes' development as the Kansas City Chiefs' starting quarterback that the team's secondary concerns haven't been the forefront of every conversation. They should be.

Five of the team's top six cornerbacks from last season are no longer on the roster. Only Steven Nelson remains.

Kendall Fuller is the organization's second-most important player since he's the Chiefs' top cover man after they acquired him in March from the Washington Redskins in the Alex Smith trade.

According to Pro Football Focus' Mike Renner, Fuller graded as the league's second-best slot corner last season. He'll now be forced to play some outside corner and move back to nickel in certain defensive packages.

"I think it's the same skill set; it's just a different area of the field," Fuller said, per the Chiefs' official site. "Truth be told I felt more comfortable at corner. That's what I came in as, a corner. So, I definitely think I can step out there."

Los Angeles Chargers: RB Austin Ekeler

In just over a year, running back Austin Ekeler went from an undrafted free agent to an invaluable piece. 

"His speed, his willingness, his aggressiveness really opened people's eyes covering kicks and covering punts," Los Angeles Chargers general manager Tom Telesco said, per the Los Angeles Times' Helene Elliott. "And then when he did that, he went out for some more snaps on offense and he just took off with it."

Ekeler managed 260 yards on 47 carries and 27 catches for 279 yards during his initial campaign. His speed and versatility help put the team's backup running back and core special teams performer in an ideal spot. His complete contributions won't be seen in each week's box score, though. 

"I think that's the wrong way to look at it, actually, because if you're doing the right things on the field and you're showing the consistency, then the numbers and things will come," he said. 

A one-two punch of Melvin Gordon and Ekeler along with a loaded wide receiver corps and an improved offensive line give the Chargers a dangerous offense. 

Los Angeles Rams: LB Samson Ebukam

The Los Angeles Rams are all-in this season, as evidenced by the moves they made and attempted. 

Rams executive vice president of football operations Kevin Demoff told the Los Angeles Times' Gary Klein the organization "offered a pretty aggressive package" for Khalil Mack before the Raiders traded him to Chicago.

Why? 

Outside linebacker is the roster's one glaring weakness. Right now, Samson Ebukam is expected to keep the position afloat after being named a starter in June. 

"I think Samson Ebukam has had a tremendous spring," defensive coordinator Wade Phillips said, per Kristen Lago of the team's official site. "I just think he's learned more and more about what he can do and how to do what he does. … [He] certainly will have one of the starting positions."

On the other side of the formation, Matt Longacre and Dominique Easley are competing for playing time—which makes Ebukam's performance even more important. Aaron Donald and Ndamukong Suh will collapse the pocket; the Rams need an edge presence to finish off the quarterback at times.

Miami Dolphins: CB Bobby McCain

The Miami Dolphins used the 11th overall pick in April's draft to select defensive back Minkah Fitzpatrick. The Alabama product is a versatile piece capable of playing multiple positions, but he's at his best when working over the slot. 

The same can be said of Bobby McCain. Still, the fourth-year veteran adjusted and won the starting outside corner spot opposite Xavien Howard. 

"I think we all feel really good about it," head coach Adam Gase said, per the Palm Beach Post's Joe Schad. "We know. If Bobby ever makes a mistake, that's it. You're not going to see that same mistake again. He is a very quick learner. And he is a competitor."

McCain found work at nickel corner while the coaching staff experimented with other outside options. Cordrea Tankersley started 11 games last season yet never built the level of confidence necessary to overcome mistakes. 

As Fitzpatrick flies about the field making plays, he'll have McCain to thank for transitioning to outside corner, thus providing more opportunities at the first-round pick's preferred spot.

Minnesota Vikings: TE David Morgan

Blocking tight ends are a dying breed, even though their contributions are often essential. 

In Minnesota, Kyle Rudolph is the Vikings' starting tight end. David Morgan serves as the team's No. 2 at the position and earned a reputation as a top blocker. According to Pro Football Focus, only Rob Gronkowski and Marcedes Lewis graded better last season. 

Morgan's skill set is crucial because of the Vikings' roster configuration. The team has major concerns along its offensive front with left guard Nick Easton on injured reserve with a neck injury and center Pat Elflein just coming off the physically unable to perform list. Rashod Hill hasn't been a consistent performer at right tackle, either. 

Morgan can act as an extension of the offensive line in the run game and chip on pass-rushers. The tight end also caught 10 passes for 95 yards last season. 

"I'm not a perception guy," Morgan said during training camp about his role, per the Pioneer Press' Chris Tomasson. "I don't look at what other people think. I'm trying to do my best no matter what the play is."  

New England Patriots: CB Eric Rowe

New England Patriots head coach Bill Belichick surprised everyone last season when he started Eric Rowe over Malcolm Butler in Super Bowl LII. Butler is gone, and Rowe took over starting cornerback duties opposite Stephon Gilmore. 

"For me, my fourth year, finally getting the opportunity to go out and try to prove to everybody I can be a starter in this league, too," Rowe said, per The Athletic's Jeff Howe. "There's nothing wrong with being a nickel guy, coming off the third corner, but now I get to step up my game." 

Rowe provides a different dynamic on the outside thanks to his size. He's 6'1" and 205 pounds with the ability to match up against bigger receivers or detached tight ends. Gilmore (6'1", 202 lbs) and Rowe have similar physical profiles, providing the Patriots with a potential advantage. 

"All players are different, but when there are certain similarities that give you an interchangeability between two players, then that lessens the need to one guy always doing one thing and the other guy always doing another thing," Belichick said, per NESN.com's Doug Kyed. 

New Orleans Saints: CB Ken Crawley

New Orleans Saints cornerback Marshon Lattimore experienced so much success during his rookie campaign that the fact that the defense featured another new full-time starter in Ken Crawley didn't draw much attention. 

Lattimore won NFL Defensive Rookie of the Year honors and is already being placed among the league's best young defenders. This means he'll match up against the each team's top wide receiver. 

"If they are the best receivers in the league and I'm shutting them down, that has to say something about my game, too," Lattimore said, per the Times-Picayune's Amos Morale III. 

As a result, Crawley will almost certainly see more targets this fall because of Lattimore's burgeoning reputation, since offenses will avoid the latter. This approach will feed directly into the strength of the Saints' improved defense, because Crawley allowed the lowest catch rate in the red zone last season, according to Pro Football Focus. 

With Patrick Robinson in the mix as the new nickel corner, the Saints secondary will be one of the most difficult to face this year. 

New York Giants: DE Dalvin Tomlinson

What's old is new again for New York Giants defensive lineman Dalvin Tomlinson, who left Alabama's 3-4 defensive scheme to play defensive tackle in last year's 4-3 front only to have the scheme switch again in his second professional season. 

"We're shooting more gaps, and it's more attacking, more going after it rather than waiting and seeing what's given to you," Tomlinson said of coordinator James Bettcher's system, per NJ.com's Ryan Dunleavy. "I love the scheme. It reminds me of Alabama's scheme. You can say you have less responsibilities, but a little more at the same time."

Nick Saban's staff prepared Tomlinson well for the NFL. The defensive lineman plays with natural leverage (as a high school state wrestling champion), impeccable hand placement and overall technique. He quickly developed into one of the league's best run defenders, according to Pro Football Focus. 

When a good run defender plays alongside the league's best at the point of attack, Damon Harrison, his contributions don't seem as significant. But this duo, along with rookie B.J. Hill, will make running the ball extremely difficult for every opponent.

New York Jets: WR Robby Anderson

The New York Jets must provide the right talent around quarterback Sam Darnold if the rookie is to have a chance to maximize his potential. 

Wide receiver Robby Anderson can be the Jets' top target as long as he puts everything behind him after having a 2017 felony charge dropped in May and another arrest warrant rescinded just before. 

"Well, trust me, I don't like to have the Jets in that light," Anderson said, per Newsday's Colin Stephenson. "So I'm just going to let my actions speak [for themselves] and leave that behind me and focus on the future."

On the field, Anderson led the Jets last season with 941 yards and seven touchdown receptions. The Jets should rely even more on the vertical threat over Quincy Enunwa, Jermaine Kearse and Terrelle Pryor. 

"I think every year, as the years go by, I'm growing mentally," Anderson said. "I think that's the biggest thing, and especially like ... towards the end [of last season], the game started to slow down a little bit more. I'm starting to read and understand things more." 

Oakland Raiders: DE Bruce Irvin

Bruce Irvin has never been "the guy." Someone else has always been the focal point of the defense during his time with the Seattle Seahawks and Oakland Raiders. Now, the onus falls on the 30-year-old pass-rusher as the leader of an evolving defense after Mack's departure.

"At the end of the day, I've got a bunch of people counting on me; I've got a bunch of dudes looking up to me now so I just want to go out there and lead by example," Irvin said, per ESPN.com's Paul Gutierrez. "Lead by my play. Lead by how I work during the week."

Despite the roster's advanced age, the Raiders plan to lean heavily on three rookie defensive linemen—Arden Key, Maurice Hurst and P.J. Hall—with Irving serving as the primary pass-rusher.

The 2012 first-round pick no longer has to worry about playing linebacker. The Raiders want him playing in every opponent's backfield. 

"It feels good just to be able to just react and run and just play football, man," Irvin said.

Philadelphia Eagles: DT Destiny Vaeao

The Philadelphia Eagles are loaded along the defensive front, except at 1-technique. 

Timmy Jernigan required offseason back surgery and resides on the reserve/non-football injury list. The 34-year-old Haloti Ngata, meanwhile, needed time to acclimate himself to a new defensive scheme after signing with Philadelphia. 

These situations created an opening for Destiny Vaeao to earn first-team reps throughout training camp and the preseason. 

"So, this is a big year for him, just sort of putting it all together," defensive coordinator Jim Schwartz said of Vaeao, per NBC Sports Philadelphia's Dave Zangaro. "I really liked where he came out of camp last year. He's a little bit bigger now, but not overweight. He's just bigger. He's just matured a little bit more. Put a little bit more weight on."

Even if Ngata gets the nod as the starter throughout the regular season, Vaeao will be a significant contributor to the team's defensive line rotation. His increased strength at the point of attack makes him a viable alternative to Ngata after playing in 27 games the last two years. 

Pittsburgh Steelers: NT Javon Hargrave

The Pittsburgh Steelers switched gears two seasons ago when the coaching staff took a different approach to the middle of the defensive line. 

For years, the team relied on Casey Hampton, Chris Hoke and Steve McLendon as pure run-stuffers to man the nose tackle position. Everything changed with the addition of Javon Hargrave, whose game relies on quickness and disruptiveness. The third-year defender isn't just a nose tackle; he's also a part of the team's pass rush. 

"It's just about me getting better," Hargrave said, per the Pittsburgh Tribune Review's Joe Rutter. "Some of the things I'm already good at, but it's coming in here and getting better at my skills."

Hargrave's presence doesn't receive as much attention as others, because he's sandwiched between two outstanding defensive linemen in Cameron Heyward and Stephon Tuitt. But the Steelers' defensive scheme is predicated on the success of the entire defensive front. Questions at linebacker and in the secondary can hold the team back if the defensive line doesn't dominate.  

San Francisco 49ers: TE George Kittle

Some players are made to thrive in certain systems. San Francisco 49ers tight end George Kittle is one of those individuals. 

Kittle played in the same scheme at Iowa as he does now under head coach Kyle Shanahan's supervision, and it showed last season once Jimmy Garoppolo took over the offense in Week 13. The rookie caught 15 passes for 224 yards during that stretch. 

Marquise Goodwin developed into the quarterback's favorite target, but Kittle presents a somewhat unique skill set since he's both a matchup problem and a competent blocker. 

"It's rare that you have a guy who is built to block very well who also runs in the 4.5s and who is quick enough to separate," Shanahan said, per ESPN.com's Nick Wagoner. 

Tight ends have always been a featured part of the Shanahan offense. Kittle's ability to work the middle of the field will help take the pressure off the running game and short passing attack after starting back Jerick McKinnon suffered a season-ending torn ACL. 

Seattle Seahawks: RB Chris Carson

There are many reasons the offense failed quarterback Russell Wilson in recent seasons. The running game, or lack thereof, resides at the top of the list. 

As a result, the Seahawks spent this year's first-round pick on running back Rashaad Penny. However, Penny never claimed a starting spot before requiring August finger surgery. 

Chris Carson is part of the reason the franchise's top draft choice struggled to establish himself. Carson developed into the lead back throughout training camp and the preseason. 

"He had a phenomenal offseason," head coach Pete Carroll said, per Andy Patton of USA Today's Seahawks Wire. "He was really the star of the offseason in that he was just so fit, so strong and so explosive from the moment we got back."

Wilson led the Seahawks last season with 586 rushing yards while Carson recovered from a broken ankle. The second-year back is primed for a breakout campaign. 

"Chris Carson is a beast," wide receiver Doug Baldwin said, per the Seattle Times' Mike Vorel. "... He's going to be unbelievable. He's already unbelievable."

Tampa Bay Buccaneers: RB Peyton Barber

Peyton Barber is the Tampa Bay Buccaneers' starting running back. This is a somewhat startling statement, considering the organization's investment Ronald Jones. Yet, this year's second-round pick has struggled against NFL defenses. 

"We're happy with where [Jones] is," head coach Dirk Koetter said, per the Tampa Bay Times' Rick Stroud. "I'm not happy, not anything to do with him, but how we blocked some for him and, coaching-wise, we didn't do a good enough job to get him in space."

Barber ran with more authority during the preseason by averaging 5.8 yards per carry compared to Jones' pathetic 0.8 average on 28 totes. The 225-pound back is also a more physical runner than Jones, whose game is predicated on speed, even though he does run behind his pads. 

Jones isn't even listed as the team's second-string back. Jacquizz Rodgers is. 

Barber ran well in limited opportunities the last two seasons with 646 yards on 163 carries. His downhill running style is exactly what the Buccaneers need behind a suspect offensive front. 

Tennessee Titans: LB Will Compton

Avery Williamson's free-agent departure left a void at inside linebacker for the Tennessee Titans that first-round pick Rashaan Evans was supposed to fill. Evans missed the majority of training camp and all of preseason with an undisclosed injury, though. 

Will Compton claimed the starting spot next to Wesley Woodyard. 

"He's been a great teammate," head coach Mike Vrabel said of Compton, per ESPN.com's Turron Davenport. "Everybody appreciates him. He's a very knowledgeable player that rarely makes the same mistake twice. Once you show him something he usually gets it pretty good."

The veteran linebacker's understanding of the game will extend far beyond his on-field performance, because he'll give way to Evans once the rookie is ready. 

"It's rare that you find guys that are able to actually teach, especially with the competition in the film room," Evans said. "He doesn't have to teach, but the fact that he does that, it just tells you the type of ... player that he is."

Washington Redskins: WR Paul Richardson

The Washington Redskins continue to wait for Josh Doctson to develop into a true top target. Jamison Crowder, meanwhile, remains the offense's leading receiver. A second or third option is necessary for quarterback Alex Smith to excel in Jay Gruden's offensive scheme. 

Enter Paul Richardson, who signed a five-year, $40 million free-agent contract this offseason. The opportunities will be available for all three receivers to shine. 

"There's a lot of windows in this offense," Richardson told reporters. "Conceptually, there are a lot of windows. Guys are always making room for one another. There's always a guy open."

If Doctson doesn't emerge as Washington's primary outside target, Richardson is waiting in the wings as one of the league's better vertical threats. 

The 2014 second-round pick set career highs last season with 44 receptions for 703 yards and six touchdowns. He'll have every opportunity to eclipse those numbers this fall.