Fans are cautioned time and time again not to put too much stock in a player's spring training performance.

At the same time, it's hard not to take notice when a prospect previously thought a year or more away, a fringe 40-man roster candidate or a non-roster invitee puts up a noteworthy stat line.

For some of those guys, a strong spring will be their ticket to an MLB roster spot. That could mean an opportunity to break camp on the 25-man roster, or it could come later because they've put themselves on the radar this spring.

At any rate, ahead is a look at each MLB team's biggest spring training revelation.

Arizona Diamondbacks: IF Ildemaro Vargas

Spring Stats: 18-for-46 (.391), 5 XBH (1 HR), 3 BB, 3 K

At 27 years old, Ildemaro Vargas is no longer considered a prospect.

With a .250/.273/.375 line and 65 OPS+ in 33 plate appearances at the MLB level the past two seasons, he has also yet to establish himself as a big leaguer. That said, his ability to play all over the infield and his strong minor league track record still gives him a chance to carve out a role as a utility infielder.

Vargas hit .311/.348/.445 with 48 extra-base hits in 124 games at Triple-A last season, and he's now put himself on the MLB radar even if he doesn't break camp with a roster spot. 

Atlanta Braves: RHP Kyle Wright

Spring Stats: 12.0 IP, 11 H, 4 ER (3.00 ERA), 2 BB, 16 K

Kyle Wright got his first taste of MLB action down the stretch last season, allowing four hits and three earned runs in six innings out of the bullpen. Prior to that, he posted a 3.46 ERA and 1.23 WHIP with 133 strikeouts in 138 innings between Double-A and Triple-A.

As the No. 5 overall pick in the 2017 draft and one of baseball's top pitching prospects, he's always seemed a potential long-term rotation piece for the Atlanta Braves.

However, the 23-year-old has looked more MLB-ready than expected, which could mean he makes a major impact in 2019.

Baltimore Orioles: RF Austin Hays

Spring Stats: 13-for-37 (.351), 9 XBH (5 HR), 2 BB, 7 K

Austin Hays reached the majors in his first full professional season, and he looked poised to assume a sizable role in the Baltimore Orioles outfield heading into 2018.

Instead, he hit a disappointing .235/.266/.410 in 75 minor league games last season and didn't make a return trip to the majors. Still just 23, Hays has the tools to be a productive corner outfielder, and he's been the team's best hitter this spring. 

Despite that, he was sent to minor league camp last week, as new manager Brandon Hyde cited the need for further development: "We're going to always do what's best for the player. When it's a prospect-type player, their development is the most important thing. When you're talking about some of those guys, you're talking about guys who in our eyes, haven't quite finished their development."

Unless he falls flat again in Triple-A, he should be the team's everyday right fielder before the All-Star break.

Boston Red Sox: LHP Darwinzon Hernandez

Spring Stats: 10.0 IP, 7 H, 1 ER (0.90 ERA), 5 BB, 12 K

Bleacher Report's No. 2 prospect in the Boston Red Sox system, left-hander Darwinzon Hernandez has looked ready for MLB action this spring.

That's saying something, considering the 22-year-old has thrown just six innings at Double-A and spent the bulk of the 2018 season with High-A Salem.

This isn't the first time he's turned heads since the end of last season, though. Working in relief during the Arizona Fall League, he posted a 1.59 ERA with an eye-popping 24 strikeouts in 11.1 innings.

The Red Sox will continue to stretch him out as a starter in the minors, but he could be ready to make an impact in a multi-inning relief role sometime soon.

Chicago Cubs: RHP Allen Webster

Spring Stats: 9.0 IP, 4 H, 2 ER (2.00 ERA), 3 BB, 10 K

The fact our vast photo database does not even have a picture of Allen Webster in a Chicago Cubs jersey speaks to what an afterthought he was entering camp.

A former top prospect in the Los Angeles Dodgers system who was traded to the Boston Red Sox in 2012's Adrian Gonzalez/Carl Crawford/Josh Beckett blockbuster, Webster has never put it together at the MLB level despite quality stuff.

The Cubs scooped him up in minor league free agency last year, and he posted a 2.65 ERA with 24 strikeouts in 17 minor league innings before he worked three innings out of the MLB bullpen as a September call-up.

Now, the 29-year-old will likely head to Iowa, where he could be one of the first players called upon when a spot opens up in the bullpen.

Chicago White Sox: RHP Ryan Burr

Spring Stats: 7.2 IP, 5 H, 1 ER (1.17 ERA), 0 BB, 9 K

Ryan Burr was lights-out in the upper levels of the minors last season, posting a 2.45 ERA, 1.15 WHIP and 51 strikeouts in 51.1 innings between Double-A and Triple-A.

He made his MLB debut in late August, but he was shelled. Over 9.2 innings, he allowed 12 hits, six walks and eight earned runs for an unsightly 7.45 ERA.

With a fastball that touches 99 and a quality slider, he has prototypical late-inning stuff. It also plays up thanks to some deception in his max-effort delivery.

After his spring performance, it's increasingly likely he'll break camp with a spot in the bullpen.

Cincinnati Reds: C Kyle Farmer

Spring Stats: 12-for-31 (.387), 8 XBH (2 HR), 2 BB, 7 K

Curt Casali's offseason hip surgery opened the door for Kyle Farmer to break camp as the Cincinnati Reds backup catcher.

He appears to be aware of the opportunity in front of him. 

A former Los Angeles Dodgers prospect acquired in the same deal that brought Alex Wood and Yasiel Puig over this offseason, Farmer hit .288/.333/.451 with 32 extra-base hits in 79 games at Triple-A last season.

Aside from his work behind the plate, he also spent time at all four infield positions in the minors. That added versatility will benefit him as he tries to carve out an MLB bench role.

Cleveland Indians: OF Oscar Mercado

Spring Stats: 16-for-40 (.400), 7 XBH (3 HR), 1 BB, 7 K

The Cleveland Indians acquired Oscar Mercado from the St. Louis Cardinals last summer in exchange for Conner Capel—a rare midseason prospect swap.

After hitting a somewhat punchless .278/.349/.390 with eight home runs in 546 plate appearances at Triple-A last year, he spent the offseason working hard to retool his swing. Manager Terry Francona has taken notice.

"He worked so hard in the offseason, trying to kind of revamp his swing," Francona told T.J. Zuppe of The Athletic. "I don't care if it's spring training or not, he's swinging the bat really well."

An inactive offseason by the Indians leaves them with some combination of Greg Allen, Tyler Naquin, Jake Bauers, Jordan Luplow and the recently signed Carlos Gonzalez fighting for playing time at the corner outfield spots.

The 24-year-old Mercado has now put himself squarely in that conversation, as well.

Colorado Rockies: 2B Ryan McMahon

Spring Stats: 18-for-42 (.429), 9 XBH (2 HR), 4 BB, 6 K

The addition of veteran Daniel Murphy and the rise of prospect Garrett Hampson appeared to leave Ryan McMahon on the outside looking in for playing time on the right side of the Colorado Rockies infield.

McMahon, 24, had a chance to seize the everyday first base job last season, but he hit just .232/.307/.376 with a 31.7 percent strikeout rate in 202 plate appearances while making multiple trips to the minors.

His 18 hits and .429 batting average lead all qualified players this spring, and that might be enough to win him the starting second base job out of camp.

Regardless, he's made it extremely difficult for the Rockies to even consider sending him back down.

Detroit Tigers: CF Daz Cameron

Spring Stats: 9-for-25 (.360), 6 XBH (1 HR), 4 BB, 9 K

Daz Cameron has already been sent to minor league camp, so there's no debate about whether he'll make the Opening Day roster.

However, the toolsy outfielder looks like he'll be ready for his MLB debut at some point in 2019.

After posting a .749 OPS with 42 extra-base hits and 24 steals over three minor league levels last season, he raked to the tune of a .342/.435/.468 line with six extra-base hits in 92 plate appearances during the Arizona Fall League.

His strong spring was just one more impressive test passed with flying colors, and a hot start to 2019 in the upper levels of the minors could put him in Detroit by midseason.

Houston Astros: RHP J.B. Bukauskas

Spring Stats: 10.0 IP, 6 H, 1 ER (0.90 ERA), 5 BB, 13 K

J.B. Bukauskas is one of the reasons why the concern over the departures of Dallas Keuchel and Charlie Morton in free agency was overblown.

Not only do the Houston Astros have capable MLB-ready replacements in guys like Collin McHugh, Brad Peacock, Josh James and Framber Valdez, but their farm system boasts a number of high-ceiling arms who could be ready to contribute in 2019.

Bukauskas, the No. 15 pick in the 2017 draft, is one of those guys.

A back injury suffered in a car accident last spring limited him to 59 innings during the 2018 season. Had he remained healthy, he might have already made his MLB debut. Now, his spring performance has made it clear he'll be knocking on the door in no time, whether in the rotation or at the back of the bullpen. 

Kansas City Royals: IF Humberto Arteaga

Spring Stats: 17-for-35 (.486), 3 XBH (0 HR), 2 BB, 2 K

Humberto Arteaga entered spring training about as far off the radar as a player can get.

The 25-year-old does not appear among the Kansas City Royals' top 30 prospects on MLB.com, while Baseball America has not included him among the team's top 30 since the start of the 2013 season.

He slashed .292/.322/.386 with 26 extra-base hits in 445 plate appearances at Triple-A in 2018—the kind of stat line that earns you an invite to MLB spring training with little chance of earning a roster spot.

He's made the most of his opportunity, though, and forced his way onto the organization's radar.

While Arteaga won't steal a middle infield job away from Whit Merrifield or Adalberto Mondesi, he's positioned himself well to debut at some point in 2019.

Los Angeles Angels: RHP Jake Jewell

Spring Stats: 8.1 IP, 7 H, 2 ER (2.16 ERA), 0 BB, 8 K

When last we saw Jake Jewell, he was writhing on the ground after he suffered a gruesome ankle injury in a game against the Boston Red Sox last June.

Back in action after undergoing surgery, he's been one of the bright spots for a Los Angeles Angels team already dealing with more injuries to the pitching staff,

The 25-year-old was moved back to the bullpen last season after struggling as a starter in 2016 and 2017, and he pitched his way to the majors with a 3.08 ERA and 35 strikeouts in 38 innings between Double-A and Triple-A.

With a changeup that lags behind his fastball/slider combination, he's better suited for a relief role. Now that he's returned strong from the injury, he could be a vital part of the 2019 relief corps.

Los Angeles Dodgers: RHP Yimi Garcia

Spring Stats: 7.0 IP, 4 H, 0 ER (0.00 ERA), 1 BB, 9 K

Each spring, a handful of out-of-options players either need to impress their current teams or risk being exposed to waivers.

Yimi Garcia was one of those guys this year, but seven lights-out innings appear to have locked him into a spot in the middle of the Los Angeles Dodgers bullpen.

While the 28-year-old has struggled to stay healthy in recent years, his 3.70 ERA and 100-to-16 strikeout-to-walk ratio in 97.1 career MLB innings are clear indications of his talent and upside.

Don't be surprised if he emerges as a key setup option in a Dodgers bullpen that's once again in flux ahead of the late-inning trio of Joe Kelly, Pedro Baez and Kenley Jansen.

Miami Marlins: RHP Pablo Lopez

Spring Stats: 14.0 IP, 8 H, 2 ER (1.29 ERA), 1 BB, 11 K

Pablo Lopez opened the 2018 season on fire, posting a 0.62 ERA, 0.87 WHIP and 51 strikeouts in 43.2 innings at Double-A to earn a quick promotion to Triple-A. He was in the majors by the middle of June and wound up making 10 starts for the big club, where he earned a respectable 4.14 ERA (4.49 FIP) and 1.26 WHIP in 58.2 innings.

The 23-year-old entered camp vying for one of the open spots behind Jose Urena and Dan Straily in the Miami Marlins rotation, and he's made a compelling case.

"He was aggressive. Out of the box, good breaking ball. His change-up was good. There was nothing really bad about it," manager Don Mattingly told reporters after one of Lopez's outing earlier this spring.

The rebuilding Marlins would be silly not to reward him with an extended look.

Milwaukee Brewers: RHP Jake Petricka

Spring Stats: 9.0 IP, 6 H, 3 ER (3.00 ERA), 4 BB, 11 K

Before dealing with a series of injuries, Jake Petricka was a reliable late-inning reliever for the Chicago White Sox.

In 145 appearances from 2013-15, he posted a 3.24 ERA with 16 saves and 22 holds despite a relatively low 6.1 K/9 rate that stemmed from his approach as a contact-oriented groundball pitcher.

After regaining his health, he spent last season with the Toronto Blue Jays but struggled to a 4.53 ERA while giving up a staggering 11.6 H/9 for a 1.64 WHIP. That led to a non-tender at the start of the offseason, and the Milwaukee Brewers scooped him up on a minor league deal.

So far this spring, his heavy fastball has again been inducing grounders, and he's also been missing more bats. The Brewers have a stacked bullpen, but he's positioned himself well to earn a spot at some point.

Minnesota Twins: RHP Ryne Harper

Spring Stats: 7.0 IP, 6 H, 0 ER (0.00 ERA), 0 BB, 10 K

Despite a 2.56 ERA, 1.14 WHIP and 11.0 K/9 over the course of eight years in the minors, Ryne Harper still hasn't made his MLB debut. He was called up for three games while with the Seattle Mariners organization back in 2017, but he didn't see any action.

The soon-to-be 30-year-old split last season between Double-A and Triple-A, posting a 3.60 ERA, 1.09 WHIP and 11.9 K/9.

But still no debut.

With seven scoreless innings and 10 strikeouts against zero walks, the curveball specialist couldn't have done much more so far this spring.

New York Mets: 1B Dominic Smith

Spring Stats: 14-for-39 (.359), 3 XBH (1 HR), 4 BB, 12 K

Has Dominic Smith finally figured it out?

Ranked by Baseball America as the No. 2 prospect in the New York Mets system and the No. 71 prospect in all of baseball heading into the 2017 season, he debuted later that year with a thud.

The former first-round pick hit .198/.262/.395 with a 26.8 percent strikeout rate in 183 plate appearances. His numbers last season were similarly lackluster, and his strikeout rate climbed to 31.5 percent.

As such, his entry into the expected battle between Todd Frazier and Pete Alonso for the starting first base job has been a pleasant surprise. 

With Frazier battling injury and Alonso a likely casualty of service-time manipulation, Smith should get a prime opportunity to prove he's turned a corner at the start of the year.

New York Yankees: RHP Luis Cessa

Spring Stats: 13.0 IP, 7 H, 1 ER (0.69 ERA), 1 BB, 13 K

Luis Cessa entered camp out of options and facing a roster crunch.

It now looks like he'll break camp as the No. 4 starter in the New York Yankees rotation.

With Luis Severino and CC Sabathia both expected to start the year on the injured list and Cessa throwing brilliantly so far this spring, things have—at least temporarily—fallen into place for the 26-year-old.

Used in a variety of roles last season, he struggled to a 5.24 ERA and 1.43 WHIP in five starts and 11 relief appearances spanning 44.2 innings. Despite that lackluster performance, manager Aaron Boone sounded like he thinks the right-hander is ready to turn a corner: 

"As he dials in that command with the fastball and as he continues to mature and grow as a pitcher, he's got the capabilities of really being effective for us. He's going to play an important role for us. He’s been one of those guys that I feel has come to the point, for whatever it's worth, to perform. I feel like he's a good spot in understanding what's in front of him."

Oakland Athletics: RHP Frankie Montas

Spring Stats: 13.0 IP, 11 H, 1 ER (0.69 ERA), 3 BB, 13 K

The Oakland Athletics are banking on some of their in-house youngsters stepping up to fill the rotation behind the veteran trio of Mike Fiers, Marco Estrada and Brett Anderson.

Frankie Montas is one of those youngsters.

The 25-year-old made 11 starts last season, going 5-4 with a 3.96 ERA and 43 strikeouts in 63.2 innings. Now, he looks ready to take his game to the next level.

He's added a splitter to his repertoire this spring, and that pitch becoming a third reliable offering alongside his upper-90s fastball and plus slider would make a world of difference. 

Philadelphia Phillies: RHP Drew Anderson

Spring Stats: 12.2 IP, 6 H, 1 ER (0.71 ERA), 2 BB, 12 K

Unless injury struck, Drew Anderson never really had a legitimate shot to win a rotation spot this spring.

That said, he's pitched himself into the next-man-up slot behind the incumbent rotation of Aaron Nola, Jake Arrieta, Nick Pivetta, Zach Eflin and Vince Velasquez, and that group has enough injury history that he'll likely see plenty of MLB action. 

A 21st-round pick back in 2012, Anderson went 9-4 with a 3.87 ERA, 1.16 WHIP and 84 strikeouts in 104.2 innings at Triple-A last season. He doesn't necessarily have the stuff to thrive out of the bullpen, so Lehigh Valley once again looks like his most likely destination until a rotation spot opens up.

Pittsburgh Pirates: 3B Ke'Bryan Hayes

Spring Stats: 9-for-26 (.346), 7 XBH (2 HR), 1 BB, 7 K

Ke'Bryan Hayes is one of the best third base prospects in baseball and Bleacher Report's No. 2 Pittsburgh Pirates prospect.

Still, his performance this spring was a pleasant surprise. Over-the-fence production was one of the big question marks that surround his ultimate ceiling, so his two home runs this spring were a good sign.

The 22-year-old has not yet played above the Double-A level, where he spent all of 2018 and hit .293/.375/.444 with 31 doubles, seven triples and seven home runs.

But Jung Ho Kang and Colin Moran won't stand in his way once the Pirates deem him MLB-ready.

San Diego Padres: RHP Chris Paddack

Spring Stats: 12.2 IP, 13 H, 3 ER (2.13 ERA), 2 BB, 20 K

After Tommy John surgery stole his 2017 season, Chris Paddack returned with a vengeance in 2018.

The 6'4" right-hander split the season between High-A and Double-A, posting a 2.10 ERA, 0.82 WHIP and 120 strikeouts in 90 innings. That sent him soaring up prospect lists, and Bleacher Report named him the No. 3 prospect in a stacked San Diego Padres system.

With a strong spring showing, Paddack has a strong chance to break camp with a rotation spot.

Even if he does start the year in the minors, expect him to make 25-plus starts and be leading the staff by midseason.

San Francisco Giants: RHP Trevor Gott

Spring Stats: 6.2 IP, 4 H, 0 ER (0.00 ERA), 3 BB, 10 K

Once upon a time, Trevor Gott was viewed as the future closer of the Los Angeles Angels.

He was one of the key pieces acquired in the deal that sent closer Huston Street to the San Diego Padres, and he debuted with a 3.02 ERA in 48 appearances during the 2015 campaign.

Things have gone downhill since then.

He was traded to the Washington Nationals for Yunel Escobar following his strong rookie season. Over the past three years in the nation's capital, he posted a 7.39 ERA in 33 appearances.

But the San Francisco Giants acquired him in February after he was designated for assignment, and he's made a strong case for a bullpen spot. Still just 26 years old and under team control through 2023, he may wind up becoming a real diamond in the rough.

Seattle Mariners: CF Braden Bishop

Spring Stats: 11-for-29 (.379), 4 XBH (3 HR), 2 BB, 5 K

A broken arm cut Braden Bishop's 2018 season short in July, and he headed into camp accompanied by more marquee prospects after the Seattle Mariners spent the offseason wheeling and dealing. 

His .379 batting average and three home runs were enough for the Mariners to take him on their trip to Japan, and he could be ready to seize the fourth outfielder job if Ichiro doesn't maintain his hold on a roster spot. 

Bishop, 25, has the hit tool and wheels to develop into a leadoff hitter, and he's also a standout defender in center field. His strong return from injury has thrust him into 2019's roster picture.

St. Louis Cardinals: 1B Rangel Ravelo

Spring Stats: 15-for-45 (.333), 4 XBH (1 HR), 3 BB, 6 K

The St. Louis Cardinals always seem to receive a significant contribution from an older minor leaguer who has exhausted his prospect status without ever carving out an MLB role.

Jose Martinez was that guy. Luke Voit was that guy before he was traded to the New York Yankees.

Could Rangel Ravelo be that guy in 2019?

The 26-year-old spent last season at Triple-A Memphis, hitting .308/.392/.487 with 19 doubles, 13 home runs and 67 RBI in 398 plate appearances.

He has the same defensive profile as Martinez (who doesn't have a spot in the starting lineup because of his inefficiency in the field), so he'll face an uphill battle for MLB playing time. Offensive talent tends to rise to the surface in today's game, though.

Tampa Bay Rays: LHP Hoby Milner

Spring Stats: 9.1 IP, 6 H, 2 ER (1.93 ERA), 0 BB, 12 K

The Tampa Bay Rays acquired Hoby Milner from the Philadelphia Phillies for cash considerations last July, and he posted an inauspicious 6.75 ERA in four appearances before the team sent him to Triple-A.

His 3.77 ERA and 21-to-3 strikeout-to-walk ratio in 14.1 minor league innings for Durham were reason enough to keep an eye on him this spring, and he's excelled while again displaying terrific command.

Manager Kevin Cash made a point to mention Milner's solid spring while talking to reporters over the weekend. Even if he doesn't break camp with a bullpen spot, he has a good chance to see MLB action at some point in 2019.

Texas Rangers: RHP Jason Hammel

Spring Stats: 8.2 IP, 4 H, 1 ER (1.04 ERA), 2 BB, 10 K

The resurgence of a healthy Hunter Pence (15-for-39, 5 2B, 3 HR) has been plenty surprising, and a healthy Drew Smyly (5.1 IP, 3 H, 1 ER, 7 K) looks poised for a nice bounce-back season. But Jason Hammel's push to claim a rotation spot is easily the biggest spring revelation for the Texas Rangers.

After a terrific run with the Chicago Cubs, Hammel struggled to a 5.59 ERA and 1.51 WHIP in 307.1 innings over the course of a two-year deal with the Kansas City Royals.

He was bought out of his 2019 option for $2 million and forced to settle for a minor league deal with the Rangers, who have enough question marks in the rotation that he has a real shot to win a spot.

If he doesn't make an MLB roster, the 36-year-old has already indicated he'll hang it up rather than report to Triple-A.

Toronto Blue Jays: RHP Sam Gaviglio

Spring Stats: 14.0 IP, 7 H, 2 ER (1.29 ERA), 4 BB, 15 K

Forced into the MLB rotation out of necessity last season, Sam Gaviglio posted a 5.31 ERA, 1.44 WHIP and 105 strikeouts in 123.2 innings.

The 28-year-old has bounced around a fair amount in his career, spending time with the St. Louis Cardinals, Seattle Mariners and Kansas City Royals before landing on the Toronto Blue Jays last March. 

They've given him a long look this spring, and he's made the most of the opportunity.

His fastball and slider would play out of the bullpen, but the Blue Jays may ultimately opt to keep him stretched out in Triple-A, especially considering the injury history of Matt Shoemaker, Aaron Sanchez and Clay Buchholz.

Washington Nationals: 3B Jake Noll

Spring Stats: 13-for-36 (.361), 6 XBH (2 HR), 4 BB, 8 K

Top prospects Victor Robles (13-for-37, 2 HR, 6 SB) and Carter Kieboom (9-for-31, 3 2B, 3 HR) have lived up to the hype this spring, but that's not exactly a revelation.

On the other hand, the play of third baseman Jake Noll has been a pleasant surprise.

Unranked among the team's top 30 prospects on MLB.com, the 25-year-old hit .291/.341/.412 with 20 doubles, 11 home runs and 72 RBI between High-A and Double-A last season.

In a top-heavy farm system, Noll has a chance to emerge as one of the team's better position-player prospects this season and put himself on the MLB radar in the process.

All stats courtesy of Baseball Reference and accurate heading into games Monday.