Every Team's Prospect Most Likely to Make MLB Debut on Opening Day

One of the most exciting storylines each spring training is seeing which prospects will play their way on to the Opening Day roster.

In 2020, we saw the Chicago White Sox break camp with Luis Robert as the starting center fielder, while the San Diego Padres carried an unheralded prospect in Jake Cronenworth as a bench piece.

Both players had yet to make their MLB debuts, yet they were part of the Opening Day roster and quickly developed into key contributors as the season progressed.

With that in mind, we set out to identify the one prospect in each MLB organization most likely to make his MLB debut on Opening Day. Players were selected based on their path to an MLB role and proximity to the majors in terms of their development.

Since players who have not yet made their MLB debut were the focus, guys like Ke'Bryan Hayes, Ian Anderson, Randy Arozarena, Cristian Pache, Alex Kirilloff, Dylan Carlson, Sixto Sanchez, Nick Madrigal and several others who have already debuted but still have prospect eligibility were not included.

It's a mix of big-name prospects, under-the-radar potential contributors and Rule 5 selections that should serve as a nice look ahead at what to watch for this spring.

Baltimore Orioles: RHP Michael Baumann

With only John Means and Alex Cobb locked into rotation spots, Baumann is one of a handful of young pitchers who figures to get a long look this spring. The 25-year-old reached Double-A during a breakout 2019 season that saw him post a 2.98 ERA in 124 innings while raising his strikeout rate from 7.3 to 10.3 per nine innings. He has little left to prove in the minors.

Boston Red Sox: RHP Connor Seabold

Acquired from Philadelphia in a deal that sent Brandon Workman and Heath Hembree the other way, Seabold immediately became one of the most MLB-ready arms in a thin Boston system. He doesn't have overpowering stuff, but he does a great job keeping hitters off balance. The 24-year-old turned heads in the Arizona Fall League in 2019, logging a 1.06 ERA and a 22-to-3 strikeout-to-walk ratio in 17 innings.

New York Yankees: LHP Trevor Lane

A 10th-round pick in 2016, Lane has been quietly effective over four minor league seasons with a 2.38 ERA and 1.10 WHIP in 134 appearances. The 26-year-old southpaw recorded more than three outs in 28 of 44 appearances in 2019, and he was equally effective against righties (.164 BA, .519 OPS) and lefties (.177 BA, .522 OPS).

Tampa Bay Rays: RHP Brent Honeywell

Honeywell has appeared on the Baseball America Top 100 prospect list to begin each of the last five seasons, peaking at No. 14 in 2018, but injuries have derailed his ascent. The 25-year-old has not thrown a professional inning since 2017, with Tommy John surgery and a fractured elbow costing him the last two seasons. He had reached Triple-A before his prolonged absence, so it's not inconceivable that he could still be viewed as MLB-ready even after the layoff.

Toronto Blue Jays: IF/OF Logan Warmoth

The No. 22 overall pick in the 2017 draft, Warmoth has failed to live up to expectations and been lost in the shuffle of a Toronto system that is loaded with middle-infield talent. He's no longer the shortstop of the future, but that could actually work in his favor. He'll be more likely to snag a bench spot than someone the team is intent on developing as an everyday player. The 25-year-old added to his defensive versatility by playing some outfield in 2019, and he could push Santiago Espinal for the utility spot with a good spring.

Chicago White Sox: OF Micker Adolfo

Adolfo was a prospect on the rise in 2018 when he posted an .833 OPS with 30 extra-base hits in 79 games as a 20-year-old at High-A, but he missed the last two months of the season following Tommy John surgery. That was followed by an injury-plagued 2019 in which arthroscopic elbow surgery limited him to just 39 games. He's lacking in upper-minors experience, but he's also out of minor league options and has enough upside that he's unlikely to clear waivers

Cleveland: RHP Trevor Stephan (Rule 5 pick)

A third-round pick in 2017, Stephan will have a chance to crack the Cleveland bullpen as a Rule 5 pick after racking up 275 strikeouts in 238.2 innings during his time in the New York Yankees farm system. He has been developed primarily as a starter to this point, but his fastball-slider combination and deceptive delivery should allow his stuff to play up in a relief role.

Detroit Tigers: OF Akil Baddoo (Rule 5 pick)

The Tigers carried toolsy outfielder Victor Reyes as a Rule 5 pick in 2018 and he has developed into a solid contributor, so don't be surprised if Baddoo sticks. He has shown solid on-base skills with a 13.8 percent walk rate and .357 career on-base percentage, and he also has the wheels to cover ground in center field and to steal a base. All of that fits well in the reserve outfielder role he is likely to fill in 2021.

Kansas City Royals: RHP Jackson Kowar

The Royals surprised more than a few people by putting Brady Singer in the Opening Day rotation a year ago, so it's not out of the question to think another of their young pitching prospects could get the nod. Kowar looks like the next man up after posting a 3.52 ERA and 144 strikeouts in 148.1 innings while reaching Double-A in 2019, and he could be the best of the bunch thanks to one of the best changeups in the minors.

Minnesota Twins: RHP Jhoan Duran

As it stands, the Twins have two spots to sort out in the starting rotation behind Kenta Maeda, Jose Berrios and Michael Pineda. Sinkerballer Randy Dobnak has the inside track for one of them, but the other is completely up in the air. With an upper-90s fastball that touches triple digits and a hard splitter, Duran has the power stuff to be a force if he can consistently show a viable change of pace. A strong spring could put the 22-year-old on the MLB roster.

Houston Astros: OF Chas McCormick

McCormick is currently one of just four outfielders on Houston's 40-man roster, and that includes Yordan Alvarez who will likely be the primary DH once again. That doesn't guarantee him a spot on the roster, but he's earned a look. The 25-year-old hit .269/.386/.432 with 26 extra-base hits, 16 steals and more walks (67) than strikeouts (62) in 110 games between Double-A and Triple-A in 2019, and he can play all three outfield spots.

Los Angeles Angels: RHP Jose Alberto Rivera (Rule 5 pick)

The Astros gave Rivera a $10,000 bonus as a 19-year-old international prospect in 2016, and he has taken a huge step forward with his stuff since entering pro ball. He tallied 95 strikeouts in 75.2 innings at Single-A in 2019 while showing a 70-grade fastball and two quality off-speed offerings. He profiles as a multi-inning weapon and could wind up being the best of this year's Rule 5 selections.

Oakland Athletics: OF Ka'ai Tom (Rule 5 pick)

Tom filled up the stat sheet in the upper levels of the Cleveland system in 2019, hitting .290/.380/.532 with 27 doubles, 10 triples, 23 home runs and 86 RBI in 132 games. The Athletics have hit on a Rule 5 outfielder before with Mark Canha, and the departure of Robbie Grossman in free agency gives Tom a clear path to a spot on the MLB roster.

Seattle Mariners: RHP Sam Delaplane

The Mariners found a diamond in the rough when they selected Delaplane out of Eastern Michigan in the 23rd round of the 2017 draft. The 25-year-old posted a 2.23 ERA with an eye-popping 120 strikeouts in 68.2 innings between High-A and Double-A in 2019, and then punched out 15 batters in eight innings in the Arizona Fall League for good measure. With his wicked fastball-slider combination, he could fill a setup role in Seattle in 2021.

Texas Rangers: RHP Brett de Geus (Rule 5 pick)

With a history of holding onto Rule 5 picks, there's a good chance the rebuilding Rangers will give de Geus every opportunity to stick in 2021. The 23-year-old showed vastly improved stuff in 2019 while logging a 1.75 ERA, 0.94 WHIP and a 72-to-13 strikeout-to-walk ratio in 61.2 innings between Single-A and High-A. It's a big jump to the majors, but he has the stuff to be a quality relief arm, even if he's relegated to mop-up duty in his debut.

Atlanta Braves: LHP Philip Pfeifer

Outfielder Drew Waters might be the popular answer here, but he has a lot of work to do refining his approach after striking out 164 times at a 28.6 percent clip in 2019. The Braves stretched Pfeifer out as a starter in 2019 and he responded with a 2.97 ERA and 159 strikeouts in 133.1 innings in the upper levels of the minors. However, he still fits best in the bullpen due to his lack of a reliable third pitch, and he'll get an extended look this spring.

Miami Marlins: RHP Edward Cabrera

The trio of Sandy Alcantara, Pablo Lopez and Sixto Sanchez gives the Marlins an extremely bright future, and there's another high-octane arm on the way in Cabrera. The 22-year-old has an electric fastball-slider combination, and he uses his big 6'4" frame to create a good downhill plane. The Marlins may ultimately play the service-time game with him, but he's the type of talent who could force the team's hand with a lights-out spring.

New York Mets: RHP Sam McWilliams

McWilliams has been well-traveled in his pro career, going from Philadelphia to Arizona to Tampa Bay to Kansas City and then back to Tampa Bay before signing a one-year, $750,000 MLB deal as a free agent this offseason. A towering 6'7" right-hander who still has some intriguing projection potential, he logged three straight seasons with at least 130 innings prior to 2020 and could be a back-of-the-rotation innings-eater down the line. For now, he'll likely fill a middle-relief role for the Mets with some multi-inning potential.

Philadelphia Phillies: IF Kyle Holder (Rule 5 pick)

Viewed as the best defensive shortstop in the 2015 draft class, Holder was taken No. 30 overall by the Yankees with the hope that his bat would develop enough for him to be an everyday player. With a punchless .264/.317/.350 line in 1,744 minor league plate appearances, it's now fairly clear that's not going to happen. Still, his glove should be enough for him to win a bench role in Philadelphia as a Rule 5 pick.

Washington Nationals: LHP Sam Clay

The Nationals signed Clay to an MLB deal in November that comes with a $575,000 guarantee, so there's a good chance we'll see him in the majors at some point during the upcoming season. The 27-year-old has a 3.97 ERA and 9.6 K/9 in 405.1 minor league innings, and he struck out 26 batters in 22.2 innings at Triple-A in 2019.

Chicago Cubs: RHP Gray Fenter (Rule 5 pick)

The Cubs will have multiple bullpen spots up for grabs this spring, and Fenter will receive a long look as a Rule 5 selection from the Baltimore organization. In 2019, he went 8-2 with a 1.81 ERA, 1.10 WHIP and 123 strikeouts in 94.1 innings while holding opposing hitters to a .185 batting average at Single-A. He has the stuff to thrive in a bullpen role with an upper 90s fastball and a plus curveball, and he could be a pleasant surprise.

Cincinnati Reds: RHP Ryan Hendrix

With a 70-grade fastball and plus breaking ball, Hendrix has racked up 12.2 K/9 in 172.2 innings since he was selected in the fifth round of the 2016 draft. After trading closer Raisel Iglesias and non-tendering Archie Bradley, and with Michael Lorenzen expected to move into the rotation, there will be multiple holes to fill in the Cincinnati bullpen this spring, and Hendrix already has a spot on the 40-man roster.

Milwaukee Brewers: IF/OF Jamie Westbrook

After hitting .281/.358/.451 with 26 doubles, 16 home runs and 77 RBI in 128 games between Double-A and Triple-A in 2019, Westbrook signed a minor league deal with the San Francisco Giants last winter. He ended up playing Indy ball after the MiLB season was canceled, posting a .900 OPS with 12 extra-base hits in 27 games for Sugar Land, and he'll have a chance to win a bench spot in Milwaukee with a strong spring.

Pittsburgh Pirates: RHP Luis Oviedo (Rule 5 pick)

Oviedo has the highest ceiling of any of this year's Rule 5 selections, but he's still lacking in overall feel for pitching, and that's going to make his jump from Single-A to the MLB roster a trying one. If the Pirates stick it out, they could wind up with a middle-of-the-rotation starter down the line thanks to an upper-90s fastball and three playable off-speed pitches all from a strong 6'5", 235-pound frame.

St. Louis Cardinals: IF Kramer Robertson

An early selection for a college senior as a fourth-round pick in 2017, Robertson has quickly climbed the minor league ranks following a standout career at LSU. The 26-year-old posted a .360 on-base percentage with 27 extra-base hits and 14 steals between Double-A and Triple-A in 2019, and he could be the next in a long line of productive, homegrown utility infielders in St. Louis.

Arizona Diamondbacks: RHP J.B. Bukauskas

If the D-backs decide to commit to using Bukauskas as a reliever, he could make a strong case for a spot in the MLB bullpen in 2021. The No. 15 overall pick in the 2018 draft was acquired in the Zack Greinke blockbuster, and while he has been developed as a starter to this point, his inconsistent command and max-effort mechanics have always looked destined for the bullpen. His dynamic fastball-slider combo gives him closer upside as a reliever.

Colorado Rockies: RHP Jordan Sheffield (Rule 5 pick)

The No. 36 overall pick in the 2016 draft after pitching alongside Atlanta Braves right-hander Kyle Wright at Vanderbilt, Sheffield is the younger brother of Mariners starter Justus Sheffield. After flopping as a starter, he moved to the bullpen in 2019 and posted a 3.27 ERA and 12.1 K/9 with 13 saves in 49 appearances. Those strong surface-level numbers came with an ugly 7.0 BB/9, but he has the stuff to succeed in a relief role.

Los Angeles Dodgers: OF DJ Peters

With an imposing 6'6" frame and prolific raw power, Peters has slugged 92 home runs in four minor league seasons. He strikes out a ton with a 30.9 percent strikeout rate, but he can also work a walk with a solid .363 on-base percentage in his career. Add in his solid outfield defense, which plays at all three spots, and he's essentially Joey Gallo-lite. With Joc Pederson and Enrique Hernandez both hitting free agency, there's at least one open spot for an outfielder on the MLB roster.

San Diego Padres: LHP MacKenzie Gore

The Padres have not been shy about putting their top prospects on the Opening Day roster, doing so with Chris Paddack, Fernando Tatis Jr. and Jake Cronenworth all breaking camp with a spot in recent years. The Yu Darvish and Blake Snell trades have signaled their all-in approach to the 2021 season, so who's to say they won't also throw uber-prospect MacKenzie Gore into the rotation mix? The future ace has been a man among boys in the minors to this point in his pro career.

San Francisco Giants: IF Jason Vosler

Vosler turned in three straight 20-homer seasons in the minors prior to 2020, including a stellar 2019 season at Triple-A when he hit .291/.367/.523 with 19 doubles, 20 home runs and 63 RBI in 116 games. The Giants signed him to an MLB deal as a minor league free agent in November, and he could see plenty of playing time as the backup to oft-injured Evan Longoria at third base.

All stats courtesy of Baseball Reference and FanGraphs unless otherwise noted.