Every team has one of those guys -- you know, a player with the "what if" attached to his name. What if he stays healthy? What if he puts it all together? What if he learns to lay off that slider off the plate or just throws a few more strikes?
Listed below are one of these type of players for each American League team, those guys facing a make-or-break season with their current organization given their age and experience -- and the kind of players who can help make a season for a team if they come up big.
AL East
Baltimore Orioles -- Dylan Bundy, RHP
At one point, Bundy was regarded as the best pitching prospect in the game. Drafted fourth overall in 2011, Bundy made his professional debut in 2012 and rocketed through the minors, even making two relief appearances for the Orioles that September when he was still just 19. He signed a major league contract out of high school, however, so despite missing most of the past three seasons with injuries, Bundy is now out of options. He'll have to make the Orioles out of spring training, clear waivers (which won't happen) or be traded if the Orioles don't keep him on the 25-man roster.
Boston Red Sox -- Joe Kelly, RHP
Kelly throws a mid-90s sinking fastball but lacks the command and secondary pitches to succeed as a starter -- despite which he keeps getting opportunities to start. Some of that is because of a fluky 2.28 ERA he had in 15 starts with the St. Louis Cardinals in 2013, a mark achieved despite a poor 46/34 strikeout-to-walk ratio in 87 innings. The Red Sox actually demoted him to Triple-A Pawtucket midseason last year and he returned to post a 2.28 ERA in his final eight starts, giving him another chance in the rotation. I think his future is in the bullpen and the Red Sox have several options for the rotation, but you never know.
New York Yankees -- Starlin Castro, 2B
Castro is signed through 2019 and he'll turn 26 in a couple of weeks, but that doesn't mean the Yankees have to make a long-term commitment to him as their second baseman. He had a poor 2013 with the Cubs (-0.4 WAR) and a poor 2015 (0.6 WAR), so another bad season at the plate means three bad seasons out of four and probably a permanent sign that he's no longer the player who hit .300 his first two seasons in the majors.
Tampa Bay Rays -- Desmond Jennings, OF
Once viewed as a foundation piece for the Rays, Jennings played just 28 games in 2015 due to a knee injury and Gold Glover Kevin Kiermaier has now bumped him out of center field. He's also starting to get more expensive and his bat doesn't look as good in a corner outfield position. Could be trade bait if the Rays fall out of the race.
Toronto Blue Jays -- Drew Hutchison, RHP
Hutchison was rushed to the majors in 2012 as a 21-year-old and then missed the 2013 season after having Tommy John surgery. He made a strong return in 2014, making 30 starts, but regressed last season, ranking 88th in ERA among 89 pitchers who pitched at least 150 innings. He ranked 88th in batting average allowed and 86th in slugging percentage as right-handed batters hit .330/.384/.522 against him. He enters spring training battling Jesse Chavez and Aaron Sanchez for the No. 5 starter slot. Sanchez is best suited for the pen and Hutchison has more upside than Chavez.
AL Central
Chicago White Sox -- Avisail Garcia, RF
Scouts always liked Garcia, but I never saw much of a prospect: He never walked in the minors, didn't hit for enough power and wasn't a plus fielder. He may look like Miguel Cabrera at the plate, but he sure doesn't hit like him. The Austin Jackson signing may have sealed his fate as he's likely relegated to a backup role or part-time DH duties.
Cleveland Indians -- Trevor Bauer, RHP
Bauer will have a long major league career but he needs a breakout season if he's going to reach the star status projected when the Arizona Diamondbacks drafted him third overall out of UCLA in 2011. Bauer led the AL with 79 walks while also serving up 23 home runs; you can't do both of those things and come away unscathed and he didn't, registering a 4.55 ERA. The odd thing is he actually throws a high rate of strikes on the first pitch of plate appearances -- 21st out of 124 pitchers with at least 20 starts -- but when he fell behind 1-0 he ended up with more walks (53) than strikeouts (52). I'm not sure if he nibbles too much or doesn't trust his stuff when he falls behind or what, but there's ability here to improve.
Detroit Tigers -- Nick Castellanos, 3B
He improved his defense from "awful" to "we can live with it" and while I think his upside at the plate is ultimately limited by poor strike-zone judgment (39 walks, 152 strikeouts), he's also just 24 and scouts have always loved his swing. Certainly some breakout potential here.
Kansas City Royals -- Danny Duffy, LHP
He's a lefty with a plus fastball (averaged 93.6 mph in 2015) and a good slider and he had that 2.53 ERA in 2014 (thank you, BABIP), but he's yet to pitch 150 innings in the majors. He's not even guaranteed a rotation slot with Chris Young and Kris Medlen in the mix for the fourth and fifth spots. Duffy is one of those guys who seems likely to have a monster season at some point in his career, but he'll always fight injuries and inconsistency.
Minnesota Twins -- Alex Meyer, RHP
Meyer is different than these other guys because he has just two major league appearances, but we've also been reading about him for years, ever since the Washington Nationals selected him in the first round in 2011 and then traded him for Denard Span. He was moved to the bullpen in Triple-A last year after posting a 7.09 ERA in eight starts and had a 3.74 ERA in 55 relief innings. He still throws 95-plus and the Twins could use a power arm in their pen.
AL West
Houston Astros -- Jon Singleton, 1B
Singleton is one of four guys in the first-base picture for the Astros, along with A.J. Reed, Matt Duffy and Tyler White. Singleton hit .254/.359/.505 with 22 home runs in 102 games at Triple-A Fresno, but that terrible stint in the majors in 2014 (.168 average in 95 games) looms in the background. With Reed on the way -- if not by Opening Day, then likely at some point during the season -- and Duffy and White decent enough stopgaps, you wonder if Singleton's next chance will come somewhere else.
Los Angeles Angels -- C.J. Cron, 1B/DH
Cron will share first base and DH with Albert Pujols and could hit 25 home runs playing every day. But that power comes with a mixed blessing: He never walks, so even though he hit .262 he posted a poor .300 OBP. His strikeout rate actually isn't excessive for a power hitter and he'll hit to the opposite field, so he needs to either (a) improve his batting average, or (b) learn a little patience. His minor league track record suggests the aggressive approach isn't likely to change much.
Oakland Athletics -- Marcus Semien, SS
This is all about Semien's ability to remain at shortstop or whether his future position is second base or a utility position. After making 24 errors the first three months of last season, he trimmed that down to 11 over the final three, including just three in September. The A's believe he can stick at shortstop.
Seattle Mariners -- James Paxton, LHP
A big lefty who throws 94 and owns a four-pitch repertoire, Paxton has tantalized at times the past two seasons, but he made just 26 starts over the past two seasons due to a finger injury in 2015 and a sore shoulder in 2014. He's fighting Nate Karns for the final spot in the Mariners rotation. Like Duffy, there's big upside here if everything comes together but at some point you can't keep counting on a guy if he can't stay healthy.
Texas Rangers -- Jurickson Profar, IF
This is all about playing time. After missing the past two seasons with shoulder problems, the former top overall prospect is healthy again but is blocked by Elvis Andrus at shortstop and Rougned Odor at second base. He needs to play so the Rangers are likely to send him back to Triple-A, but if he proves he's healthy and back to what he was, you wonder if he becomes trade bait if the Rangers need to upgrade their pitching.