MLB breakout candidates: One player from all 30 teams who could make a surprise impact in 2024

The arrival of spring training means, among other things, that it's time for unbridled optimism. Major League Baseball's regular season is always good for a few surprise performances on both the team and individual levels. Part of the fun this time of the year is trying to figure out just where those breakout efforts might come from.

With that in mind, CBS Sports has made a habit of presenting one player per team every preseason who we feel is in for a better year than their previous showing. These are, as you may have guessed from the headline, our breakout picks.

Before we get to the fun stuff, let us note that we try to avoid the most obvious selections. You're not going to find Jackson Holliday and other top prospects below. Everyone knows they could impact the season in a big way – tabbing them as "breakout players" robs this exercise of its fun. Instead, you'll find a more diverse collection of players that includes some who can accurately be described as unknowns and others who have been on big-league rosters for years without hanging their star.

This approach makes us more likely to miss as a result, but in past editions of this column, we've hit on Spencer Strider, Steven Kwan, Kyle Bradish, James Outman, Drew Rasmussen, DJ LeMahieu, and Ketel Marte, among others. We'll take it.

With all that out of the way, let's get to it.

Arizona Diamondbacks: RHP Justin Martínez

It's no exaggeration to write that Martínez has elite arm strength. Last season, his heater averaged 99.9 mph and touched 102.9 mph. He also has a trapdoor splitter and a slider that each generated more than 50% whiffs between the majors and minors. You might be wondering why you haven't heard of this guy before. The answer is that he's walked nearly seven batters per innings for his career. We're not optimistic that Martínez is going to suddenly develop even fringe-average command, but his extreme velocity and bat-missing ability might be enough for him to get the job done in a league that witnessed 15 different relievers with 30-plus innings walk at least five per nine.

Atlanta Braves: LHP Ray Kerr

The Braves obtained Kerr from the Padres earlier this winter as part of the Matt Carpenter salary dump. He's one worth watching, a lefty with a 96 mph fastball and a breaking ball that last season generated more than 50% whiffs in 27 big-league innings. Kerr has struggled with his command in the past, and it wouldn't surprise us if he leans into spamming his breaking ball more often as a means of stealing strikes. For reference, Pierce Johnson, after joining the Braves in a midseason trade, threw his curve more than 75% of the time over the final two months of 2023.

Baltimore Orioles: 2B/3B Jordan Westburg

Westburg has the misfortune (in a sense) of being the talented young Orioles infielder to arrive after Gunnar Henderson and before Jackson Holliday. Life could be worse, we suppose. He showed a lot of promise during his 68-game introduction to the majors, posting a league-average OPS+ and seeing action at second and third base. We think there's more chicken on the bone here, in no small part, because Westburg showed a propensity for impacting the ball and launching it at a good angle. That tends to be a good combination. 

Boston Red Sox: 2B Vaughn Grissom

You have to take the layup when it's made available to you. Grissom, the return on Chris Sale, had his stock slip last season with a poor 23-game stretch in the majors. He posted a 78 OPS+ while confirming that he's not a viable shortstop at the big-league level. We believe he'll find redemption in Boston, where he can slot in at second base and focus on hitting -- something he's done, with the exception of those 23 games, throughout his professional career. 

Chicago Cubs: LHP Luke Little

Luke, listed at 6-foot-8, is anything but little. In addition to setting up horrible jokes like that, he may have a future in a different kind of setup role, depending on the manager's appetite for Tums. Little has walked more than five batters per nine throughout his professional career, but he's also produced absurd strikeout rates throughout. Let's put it this way: he's never averaged fewer than 13.8 K's per nine in a season – no matter the level, sample size, or role. Credit it to Little's quality one-two punch, a mid-90s heater and a swing-and-miss sweeper, as well as a crossfire delivery that – given his low and deep release point – creates hellacious angles on left-handed batters. Provided he keeps missing bats, and he should, he's going to be an intriguing left-handed option for manager Craig Counsell. 

Chicago White Sox: OF Zach DeLoach

The White Sox recently acquired DeLoach from the Mariners as part of a larger trade. We'll be upfront: we're not sure this is going to work. DeLoach has some serious plate coverage and swing-and-miss issues, the combination of which resulted in a 28% strikeout rate last season in Triple-A and figures to do even worse in the majors. There is some pop and athleticism here, however, and it's not as though the White Sox's outfield depth chart appears impenetrable.  

Cincinnati Reds: RHP Fernando Cruz

Cruz threw his splitter 36% of the time last season, ranking him eighth in usage of that particular pitch type (min. 40 innings). We'd like to see him chuck it more often heading forward, perhaps even becoming one of a handful of pitchers to clear the 40% mark. It's clearly his best pitch, registering a .094 batting average against and a 56.7% whiff rate in 2023; his mid-90s fastball, for comparison, yielded a .300 average against and 16.7% whiff rate. Otherwise, Cruz checks all the boxes of becoming a high-leverage fixture. 

Cleveland Guardians: INF Gabriel Arias

Arias is a nifty player. He's a skilled middle infielder and productive lefty hitter who … um, just so happens to bat righty. Arias is, spiritually and statistically, better thought of as a left-handed batter. He hit .275/.332/.459 against righties last season, as opposed to his abysmal .083/.168/.148 marks versus lefties. He also launched almost all of his 10 home runs to either center or right field. How do you explain the weird reverse splits? Arias seems to have a stronger aversion to change than the average human. There's nothing wrong with that, per se, but we do wonder if new Guardians manager Stephen Vogt will lean into Arias' weirdness and treat him like a left-handed hitter. If so, expect his stock to trend in the (ahem) right direction. 

Colorado Rockies: SS Ezequiel Tovar

Tovar is one of two brilliant up-the-middle defenders on the Rockies who didn't hit at all last season. (The other, Brenton Doyle, received coverage here.) We're not going to pretend we foresee Tovar turning into a great offensive player. His game possesses plenty of warts, including well below-average whiff and chase rates. We do think Tovar could fare better than he did last season, thanks to a decent ability to spray balls within the 10-to-30-degree window. Coors is often thought of as a launching pad – and it is – but that outfield is so spacious that we have to believe Tovar can and will drop in more singles this season, giving him a chance at an artificially improved line.

Detroit Tigers: RHP Sawyer Gipson-Long

The Tigers originally netted Gipson-Long from the Twins at the 2022 deadline in exchange for Michael Fulmer. Fulmer was perfectly fine for the Twins, but Gipson-Long nearly exceeded his contributions during his four-start debut stretch last September. We don't expect him to continue striking out 12 per or surrendering three or fewer earned runs per nine innings. We do think he's more interesting than he's received credit for, thanks to an offspeed-heavy approach, including a changeup with some screwball qualities and a deep release point that sees him create about 7 1/2 feet of extension from the pitching rubber. How exactly he fits into the Tigers' pitching plans this spring is to be seen – they spent the winter adding a few veteran arms to their rotation – but we suspect the Fulmer trade will be deemed a Detroit win by year's end.

Houston Astros: RHP Oliver Ortega

Forgive us for the deep cut, but the consistency of the Astros roster leaves scant room for newcomers to break through. We think Ortega has a chance to establish a foothold in a Houston bullpen that lost a few key members this winter. (To be fair, the Astros did sign Josh Hader to offset the departures.) Ortega has clocked some time with the Angels and Twins thanks to a swing-and-miss slider that generated a 45% whiff rate in 2023. Interestingly, he's been worse against righties than lefties throughout his various big-league stints. That'll need to change for him to serve as an effective middle-relief option for first-year skipper Joe Estrada.

Los Angeles Angels: RHP Kelvin Caceres

This may not register as a surprise, but the Angels lack compelling candidates. When in doubt, go with an intriguing relief arm. Caceres has good stuff and bad command. He spent most of last season in Double-A, where he punched out 14 per nine before being pushed up the ladder to Triple-A and then the majors. Caceres has walked more than six batters per nine innings throughout his professional career, so he'll have to keep missing bats if he wants to entrench himself in the Angels bullpen. 

Los Angeles Dodgers: RHP Emmet Sheehan

Sheehan appeared in 13 games last season as part of a decent introduction to the majors that saw him finish with an 89 ERA+. We're confident better days are coming. He marries a mid-90s fastball with bat-missing secondaries in his high-grade changeup and oft-critiqued slider. (He also toyed with a slower breaking ball that has sweeper qualities.) We're encouraged that Sheehan threw more strikes than you'd expect from someone who regularly issued four-plus free passes per nine during his minor-league days. Given how many injured pitchers the Dodgers have in camp, it's fair to expect Sheehan will get a real chance at changing his status from "interesting young right-hander" to "rotation stalwart."

Kansas City Royals: 3B Maikel García

Past research from Robert Orr revealed that performance against fastballs is a good indicator of future success. Consider that great news for García, who ranked in the top 10 last season in exit velocity against heaters, placing him in the same neighborhood as Shohei Ohtani, Aaron Judge, Yordan Alvarez, Corey Seager, Matt Olson, and other All-Star-caliber hitters. The catch with García is that he doesn't elevate the ball as frequently as those more famous lads do; for as long as that remains true, it's unlikely his slugging output will consistently match his innate strength. A breakout year from García, then, might resemble something from the B-Ref pages of either Yandy Díaz or William Contreras. 

Miami Marlins: OF Bryan De La Cruz

We picked De La Cruz for the Marlins last spring, too, calling his selection "easy money" because of how hard he hit the ball. He then set new career-bests in home runs (yes); walk rate (Yes); and strikeout rate (YES) … and still, somehow, finished with the worst OPS+ of his big-league career. A wiser soul than us would argue that was a win or would learn their lesson and pick someone else in this spot. Not us, no sir. We're doubling down. 

Milwaukee Brewers: 1B/OF Jake Bauers

Bauers has plenty of flaws in his game. He's not a skilled defender; he swings and misses (and strikes out) a lot, and he's sporting an 80 OPS+ through more than 400 big-league games. Yet we can understand why the Brewers are giving him a look after a season in which nearly half his batted balls had an exit velocity of 95 mph or higher. It's possible to be a bad hitter despite impacting the ball that often – an inflated strikeout rate, like Bauers', is one such way – but it's not easy. We'll take our chances with Bauer in his age-28 season. If it's another whiff, we'll give up the ghost. 

Minnesota Twins: RHP Louie Varland

Another repeat pick. We thought Varland would solidify himself as a back-end starter thanks to his deception and location. He went out there and, over the course of 68 innings, showed improved fastball velocity while striking out 4.18 batters per walk issued. Alas, Varland also surrendered more than two home runs per nine innings, thwarting his breakout attempt. The question now becomes in what role will he be used most of the year? Whatever the answer becomes, we think he's due for a better year.

New York Mets: RHP Shintaro Fujinami

We wrote more about Fujinami recently: "For as poorly as Fujinami fared in his 'rookie' year, he actually received a slight raise after making $3.25 million in 2023. Consider that a testament to his raw stuff. Fujinami averaged 98.4 mph with his fastball last season, and that undersells it, given his deep release point. He also threw two other pitches, a splitter, and a cutter, that generated more than 30% whiffs. He did a better job of generating chases following a midseason trade to the Orioles, and he'll need to continue to improve in that respect if he's going to overcome what can be charitably described as below-average command. Should there be such a thing as a make-or-break season, this would be it."

New York Yankees: C/OF Austin Wells

The book on Wells has been the same since the Yankees drafted him in 2020: he can hit, but where will he play? Nearly four years later, the answer remains "catcher." Whether or not that remains the answer heading forward, hey, who knows? We're willing to pick Wells here on the strength of what should be a league-average (or so) bat and a decent opportunity to carve out playing time. 

Oakland Athletics: INF Abraham Toro

Toro, a switch-hitting infielder now with his fourth organization, has been on a number of these lists over the years to no avail. He's now entering his age-28 season, meaning it's time to break or fade out. Toro should have a good opportunity in front of him. The A's aren't trying in the slightest, so they can give him a few hundred plate appearances without the results mattering much either way. And if Toro does actually perform? He could make for an interesting trade candidate at the deadline. 

Philadelphia Phillies: RHP Michael Mercado

It would be cheap to pick Johan Rojas and lame to select Orion Kerkering. We're rolling with Mercado, a minor offseason addition who should see big-league action at some point this summer. Mercado has a rising mid-90s fastball and a swing-and-miss curveball. This will serve as just his second season as a full-time reliever. We suspect that he'll be able to solidify himself in that role.

Pittsburgh Pirates: 3B Ke'Bryan Hayes

You have to have a darn good reason to include a player like Hayes in this kind of article after he's scored back-to-back four-win seasons. We do. He's always been a great defensive third baseman capable of striking the ball with authority, but too often, that quality contact has been driven into the ground. That changed in 2023, as he recorded an average launch angle of 11 degrees or higher in each month; for reference, he had never reached such heights for a single month in his first three seasons. Now that Hayes is lifting the ball more frequently, we think there's a chance he has a career-best offensive showing. That, combined with his stellar glove, could lift him to national relevancy.

San Diego Padres: RHP Jeremiah Estrada

Last spring, we expected Estrada to take a big role in the Cubs bullpen on the strength of his explosive rising fastball. That didn't take place. Instead, he struggled with his location in a worrisome way, walking 38 batters in 38 2/3 innings across Triple-A and the majors. Estrada was claimed off waivers by the Padres in November. We're not sure if they'll be able to help him throw more strikes, but last season was so uncharacteristic of him that we're going to hold out hope for at least another year.

San Francisco Giants: RHP Keaton Winn

Winn surfaced from the depths of the Giants system last season to appear in nine games. He showed off a high-grade splitter, chucking it 55% of the time as compared to his fastball's 26% usage rate. It's not the most conventional approach -- Kevin Gausman threw the highest rate of splitters among qualified starters, at 38% -- but it did result in a lot of whiffs and ground balls. We'd feel better about Winn's chances of sticking in a traditional rotation for the long haul if he developed a third pitch. Fortunately for us, and him, the Giants rotation will be anything but traditional.

Seattle Mariners: RHP Carlos Vargas

If there's one thing these Mariners have excelled at, it's finding useful bullpen arms. Vargas, acquired in the Eugenio Suárez trade with the Diamondbacks, has a chance to be next in line. He has massive arm strength, comfortably sitting in the upper 90s with his four-seamer, as well as a cutter that last year generated 33% whiffs overall. He did battle his command in 2023, but his track record suggests there's just enough command here to make it work at the game's highest level.

St. Louis Cardinals: INF Thomas Saggese

We've been high on Saggese dating back to last summer when the Cardinals acquired him as part of the Jordan Montgomery trade. He has a chance to be a better big-league player than a minor-league prospect. Evaluators feel he could develop into an above-average hitter, and he has enough defensive versatility to bounce around the infield (though his best position is probably the keystone). The Cardinals have gotten more mileage than arguably any other franchise with this profile. We think Saggese will continue that legacy and will find himself playing a meaningful role by summer. 

Tampa Bay Rays: RHP Taj Bradley

Maybe this is cheating since Bradley was considered a top prospect around this time last year. We won't tell anyone if you don't. He's coming off a home run-plagued introduction to the majors, but there's still much to like here. Bradley has both above-average stuff and control, and you're going to win most of the time if you bet against pitchers with those qualities, surrendering nearly two home runs for every nine innings pitched. Buy in now before he's solidified himself as a legitimate mid-rotation starter.

Texas Rangers: UTL Josh H. Smith

Smith has the unenviable job of being a young reserve on a loaded team. He's an interesting player in his own right, albeit one whose results don't indicate as much. Smith makes contact and minds the zone at above-average clips. He also showed an appreciable feel for barreling balls in 2023, and there's more juice here than folks will suspect -- his 109.8 mph max exit velocity was in line with the likes of Willy Adames and Ryan O'Hearn, among others. Playing time isn't going to be easy to come by, but given a chance, we think Smith might end up proving that he's overqualified for his role.

Toronto Blue Jays: 1B Spencer Horwitz

We don't love the idea of a first baseman with subpar power, but Horwitz is our pick based on his contact and on-base chops. In Triple-A last year, he walked more than he struck out while batting .337/.450/.495. We can envision him getting some run at DH, perhaps in a platoon capacity, and faring well enough to keep the checks coming.

Washington Nationals: LHP Robert Garcia

Garcia has been claimed off waivers twice in the past few years, first by the Marlins in 2021, then by the Nationals last August. He subsequently made the most of his 24 appearances in D.C., showcasing a feel for generating chases and ground balls with a three-pitch mix. Garcia doesn't have the kind of stuff associated with being a high-leverage arm, but a steady gig in middle relief seems within grasp for this former 15th-round pick.