Some NFL rookies hit the ground running, and others take time to develop with their respective teams. Oftentimes, injuries play a major part in delayed progression. In other cases, it's a poor roster fit. Regardless, some fans may run short on patience and prematurely label players as busts.  

Offseason adjustments, changes in position, new philosophies or roster turnover could unleash a struggling rookie who produces a breakout season. 

A coaching staff's job is to put its players in the best position to succeed; however, the talent has to meet it halfway. In some cases, it's difficult to incorporate a bad draft pick into the current system.

Looking at eight picks from the first two rounds of the 2017 draft, we'll cycle through sophomores who didn't meet early expectations and project bust or breakout 2018 campaigns. Why will some players continue to struggle? Who's primed to shake off a disappointing season?

Solomon Thomas, DE/DL, San Francisco 49ers

Draft Position: No. 3 overall

A portion of San Francisco 49ers fans have been impatient with defensive lineman Solomon Thomas' progression. The Stanford product broke out during his junior year on the collegiate level but only flashed occasionally in the pros. 

Solomon shared the probable cause for his slow start with David Lombardi of The Athletic.

"I'm overthinking," he said. "I'm not just trusting myself and going. That's the main thing for me right now, not worrying about things and just going. I definitely have some things slowing my game down. The same thing was going on my sophomore year at Stanford—I just have to let it go and play." 

Solomon hasn't been completely stonewalled up front. He logged three sacks and 34 tackles (41 combined) during his rookie campaign. Don't worry about his ability to take down the quarterback. Those numbers should rise as the team game-plans to feature him as a pass-rusher. 

According to Sacramento Bee reporter Matt Barrows, defensive coordinator Robert Saleh plans to use the 22-year-old at the "Leo" position.

Saleh spent time with the Seattle Seahawks between 2011-13 in a defensive quality control position, and he witnessed the player in the Leo role win one-on-one matchups to reach the quarterback.

Expect Thomas to let it rip in his second season and satisfy those who'd like to see his sack numbers increase for a team that needs a stronger pass rush.

Prediction: Breakout

John Ross, WR, Cincinnati Bengals

Draft Position: No. 9 overall

The Cincinnati Bengals selected wideout John Ross in the hopes of finding a complementary piece to A.J. Green in the aerial attack. However, the 40-yard-dash king only produced 12 yards on one rushing attempt that ended with a lost fumble in a Week 2 loss to the Houston Texans. He played 17 snaps and recorded zero catches during his rookie term. 

In March 2017, Ross underwent surgery to repair a torn labrum and then battled a knee injury suffered in the team's preseason finale against the Indianapolis Colts. His year ended on injured reserve with another shoulder surgery to follow. Nonetheless, other lapses contributed to his unproductive season.

Speaking to reporters, head coach Marvin Lewis called out Ross for quitting on a route in Week 10 against the Tennessee Titans: "The quarterback has to make the read and do what he does and throw the ball based on the coverage and his progression. In that case, he chose John. Made a nice throw and put the ball where it needed to be, and it ended up from you to me away. Had he been running, likely he catches it." 

Before and after that week, Ross racked up healthy scratches. It's fair to wonder if the staff felt he needed to adjust to the professional game on a mental level.

Ross worked out with former Bengal T.J. Houshmandzadeh during the offseason and seems determined to fine-tune his game. 

Nonetheless, it seems Green will lead the receivers in yards and touchdowns for the foreseeable future. When healthy, tight end Tyler Eifert takes the field as a reliable second option. Running backs Giovani Bernard and Joe Mixon should continue to flourish in the short passing game.

Quarterback Andy Dalton has thrown for 4,000-plus yards in two out of seven seasons. Ross will battle wideout Brandon LaFell for targets in an offense with one clear-cut option (Green) and several secondary pass-catchers taking what's leftover.

The No. 9 overall pick isn't in a good spot for a production boom. After playing few snaps as a rookie, he needs to further adjust to the game's speed. As a result, expect a modest contribution in 2018. 

Prediction: Bust

Mike Williams, WR, Los Angeles Chargers

Draft Position: No. 7 overall

Wide receiver Mike Williams caught 11 passes for 95 yards last year. Back and knee injuries limited his time on the field. He comes into the 2018 campaign with a better chance at putting together a bounce-back season than Ross.

For starters, quarterback Philip Rivers whips the ball all over the field. He's eclipsed 4,200 passing yards every year since 2012. Secondly, the Los Angeles Chargers have relied on his arm recently, ranking within the bottom-third in rushing yards for each of the previous four terms. 

As long as Williams stays on the field, he's primed to see ample targets alongside Keenan Allen, who has one relatively healthy season in the last three years, Tyrell Williams, Travis Benjamin and tight end Hunter Henry. 

The Clemson product averaged 18.1 yards per catch as a sophomore and scored 11 touchdowns during his senior campaign. He can stretch the field for the Chargers offense. 

The team doesn't plan on re-signing tight end Antonio Gates, who turns 38 years old in June. Rivers will develop a newfound red-zone chemistry with the 6'3", 218-pound Williams. The Chargers should have success passing inside the 20-yard line with Henry and Williams. The latter could finish with a double-digit-touchdown season.

Prediction: Breakout

Zay Jones, WR, Buffalo Bills

Draft Position: No. 37 overall

Wide receiver Zay Jones' critical drop in Week 2 against the Carolina Panthers flashed the beginning of a rough rookie campaign.

The East Carolina product finished with a 36.5 percent catch rate. Quarterback Tyrod Taylor bears some responsibility for inaccurate throws, but Jones has to find a way to secure passes in his catch radius.

The Buffalo Bills offense will undergo a transition in the upcoming season. General manager Brandon Beane traded Taylor to the Cleveland Browns in March to usher in the quarterback change. The two signal-callers vying for snaps are A.J. McCarron and Josh Allen. McCarron, who signed with Buffalo in free agency, has three NFL starts, and Allen is a rookie. 

Expect the Bills to rely on running back LeSean McCoy as a ball-carrier and receiver to carry the offense while the new starting quarterback acclimates himself to offensive coordinator Brian Daboll's system. 

No matter the quarterback, Kelvin Benjamin (6'5", 245 lbs) is a big-body receiver who should see the most targets. Tight end Charles Clay has strung together five consecutive seasons with 500-plus receiving yards. 

At best, Jones will slot into fourth among the hierarchy of pass-catchers. If Allen wins the quarterback job, he must answer criticism about his accuracy. Jones is not in an ideal spot to see a breakthrough in his sophomore year.

Prediction: Bust

Corey Davis, WR, Tennessee Titans

Draft Position: No. 5 overall

Corey Davis, the first wide receiver taken in the 2017 draft, played a little over 50 percent of the Tennessee Titans' offensive snaps. He suited up for 11 games and didn't score a touchdown during the regular season. Still, the Western Michigan product isn't a bust.

Davis missed all of October because of a hamstring injury. In the wideout's second game back against the Bengals, quarterback Marcus Mariota targeted him 10 times, though he only reeled in four catches for 48 yards. 

In the postseason, Davis saw 15 targets compared to 14 for tight end Delanie Walker. Clearly, Mariota wasn't shy about going to the rookie. He connected with Davis on two touchdown passes in the AFC Divisional Round matchup against the New England Patriots. Expect that trend to continue in a new offense under coordinator Matt LaFleur, who came over from the Los Angeles Rams.

Opposite Rishard Matthews, who doesn't have more than 65 catches in a season or a 1,000-yard campaign, Davis should emerge as a top target, especially with Eric Decker no longer in Tennessee. 

Prediction: Breakout

Curtis Samuel, WR, Carolina Panthers

Draft Position: No. 40 overall

Running back Christian McCaffrey and wide receiver Curtis Samuel—smaller quick-twitch assets capable of racking up yards in space—signaled a change in the Panthers offense. The former started slow but left his mark with 1,086 yards from scrimmage. The latter finished the season on injured reserve with an ankle injury.

Three factors are working against a breakout campaign for Samuels in 2018.

At his position, the front office added Maryland product D.J. Moore in the first round of April's draft and seven-year veteran Torrey Smith via a trade. According to the Charlotte Observer, there's no timetable for Samuel's recovery after a surgery to repair ligament damage in his ankle. Finally, previous general manager Dave Gettleman drafted him. How does he fit in new offensive coordinator Norv Turner's system? 

Samuel also logged four carries for 64 yards, but Cameron Artis-Payne will have a chance to share McCaffrey's workload in the backfield, per Max Henson of the team's official website. On Monday, Carolina announced it signed running back C.J. Anderson to a one-year deal in free agency.

Samuel played the H-back role at Ohio State. He's not a polished wide receiver, which is why his time away is a significant blow to his progression. 

You want to see more than special teams contributions from an early-second-round pick. Samuel averaged 22.1 yards per kickoff return last campaign. At best, he'll slot in the No. 4 wideout spot with low-scale expectations for 2018. 

Prediction: Bust

Gareon Conley, CB, Oakland Raiders

Draft Position: No. 24 overall

Gareon Conley only took the field for 92 snaps during the 2017 season. In a small sample, he flashed coverage skills against the New York Jets and Washington Redskins in Weeks 2 and 3. The quick-twitch cornerback nearly picked off a pass against Gang Green during the Oakland Raiders' 10-game stretch (11 weeks) without an interception.

A shin injury, which later required surgery, kept Conley off the field for all but two games. There's little doubt about his ability, but he has to play more snaps to confirm what spectators saw in a minuscule rookie sample. 

During the offseason, the Raiders gutted their cornerback unit, cutting veterans Sean Smith and David Amerson, and then allowed T.J. Carrie to hit the free-agent market. He signed with the Cleveland Browns. As a result, the coaching staff will count on Conley to lead this group alongside Daryl Worley and Rashaan Melvin, who put together one solid campaign with the Colts. 

Conley had two productive years at Ohio State and flashed in a short time in the pros. Once he's ready for action, the Raiders won't hesitate to throw him back in the fray. 

Oakland defensive backs coach Derrick Ansley spent the 2016 and 2017 seasons molding Alabama's secondary in the same role. He impressed enough to accept a defensive coordinator job with Colorado State, according to Kyle Fredrickson of the Denver Post, and then changed course and took a job on head coach Jon Gruden's staff. 

Raiders fans should feel optimistic about Ansley's ability to get the most out of Conley, who can line up inside and outside with the quickness to defend athletic wideouts all over the field.    

Prediction: Breakout

DeMarcus Walker, DE, Denver Broncos

Draft Position: No. 51 overall 

Defensive lineman DeMarcus Walker will have a difficult time adding on to his one sack from the previous year.

Initially, the Denver Broncos utilized Walker as a 3-4 outside linebacker. Defensive coordinator Joe Woods highlighted the miscast late in 2017, per BSN Denver reporter Zac Stevens.

"Joe Woods says DeMarcus Walker is ideally meant to be on the defensive line rushing the passer from the inside," he tweeted. "Says he needs to get bigger."

Denver Post reporter Nick Kosmider confirmed the team's intent to move Walker to defensive end.

Still, it's going to take more than a position change to affect his short-term career outlook. Walker, who turns 24 in September, will be bulking up his 6'4", 280-pound frame to play at a position with uncertainty. Derek Wolfe will likely start the year at defensive end. It's unclear whether Adam Gotsis will return to action after a felony rape charge. 

Walker could see expanded reps on the defensive line during training camp, but he may take on a starting role before becoming comfortable with a new spot up front. It would be best for the coaching staff to ease him into a new position.

Don't expect much from Walker in his second season, whether it's due to minimal playing time or his being thrust into a starting position after taking the field for just 100 snaps in a different role as a rookie.

Prediction: Bust