From top prospects to Quad-A veterans, here are a dozen unproven hitters PECOTA projects to make an impact in 2019 if they get the opportunity …

Pete Alonso, New York Mets

Top Three Same-Age Comps: Rhys Hoskins, Chris Carter, A.J. Reed

Alonso is a 24-year-old should-be designated hitter on an NL team that didn’t call him up last season and PECOTA isn’t sure he’ll hit .225. So why is he on this list? Here’s everyone projected for a higher isolated power than Alonso in 2019: Mike Trout, Joey Gallo, J.D. Martinez, Giancarlo Stanton, Aaron Judge. That’s it. Alonso’s skill set is riddled with red flags, but he’s hit .290/.381/.560 in three minor-league seasons, including .285/.395/.579 with 36 homers last year. He figures to arrive in New York as soon as his free agency has been delayed for another year, and PECOTA assigns Alonso the second-highest “breakout” rate (25 percent) among expected regulars. The top-comp roller-coaster of Hoskins/Carter/Reed seems perfect.

Rafael Devers, Boston Red Sox

Top Three Same-Age Comps: Addison Russell, Xander Bogaerts, Ryan Zimmerman

Devers took a clear step backward last season following a very impressive 58-game rookie showing, yet still managed to be an average-ish regular for the best team in baseball at age 21. PECOTA sees him bouncing back this season, projecting Devers for the Red Sox’s third-highest slugging percentage behind only J.D. Martinez and Mookie Betts (and ahead of, among others, no. 2 same-age comp Xander Bogaerts). It’s possible that Devers’ true breakout is another year or two away—his plate discipline could use some work and despite the big-league experience he’s the same age as a typical top-101 prospect—but PECOTA is still very much a believer in his long-term upside.

Yandy Diaz, Tampa Bay Rays

Top Three Same-Age Comps: Kevin Youkilis, Max Muncy, Eric Campbell

Named to my Quadruple-A All-Star team in back-to-back seasons, Diaz checks three key boxes to look for in any breakout candidate. First, his baseline projection is decent (.263/.352/.371, 1.4 WARP). Second, his playing time outlook changed for the better with a trade from Cleveland to Tampa Bay. Third, there’s a specific reason to think he’s capable of dramatically out-producing his projection, as Diaz’s high ground-ball rates have kept his high hard-hit rates from leading to more power. At worst, he’s a versatile corner defender with good on-base skills. At best, he’ll add power to that profile by elevating the ball and could turn into an impact hitter, like late-blooming top comps Kevin Youkilis and Max Muncy.

Vladimir Guerrero Jr., Toronto Blue Jays

Top Three Same-Age Comps: Jason Heyward, Mike Trout, Carlos Correa

Guerrero would have been in the majors last summer if not for service-time suppression. Instead, he never got a call-up after hitting .381/.437/.636 at Double-A and Triple-A, and the no. 1 prospect in baseball will begin this season back in the minors to “work on his defense” until the Blue Jays gain another year of team control. PECOTA projects Vladito as the majors’ 11th-best hitter, despite the fact that he’ll be 19 for another month and has yet to actually play in the majors. It’s an unheard-of projection for any rookie, let alone one entering his age-20 season. Not only does Guerrero project as MLB’s best 20-year-old (ahead of fellow phenom Juan Soto), his projected .310/.370/.527 line is better than every hitter under 26.

Eloy Jimenez, Chicago White Sox

Top Three Same-Age Comps: Oswaldo Arcia, Christian Yelich, Wil Myers

Toronto holding back Guerrero for service-time reasons provides cover for Chicago doing the same with Jimenez, who hit .337/.384/.577 at Double-A and Triple-A last season without getting a call-up. Jimenez will likely begin this season back in the minors, but PECOTA thinks he’ll be ready to make a middle-of-the-order impact whenever the White Sox finally let him debut, projecting the no. 4 overall prospect at .281/.321/.471. If not for Guerrero’s otherworldly projection that Jimenez line would be eye-catching for a 22-year-old rookie. His relative lack of plate discipline is a potential red flag that shows up in some of his top comps, but Jimenez’s low strikeout rate attached to 80-grade raw power is a rare combination.

Ramon Laureano, Oakland Athletics

Top Three Same-Age Comps: Derek Fisher, Joe Benson, Lewis Brinson

Laureano had an eye-opening 48-game debut with the A’s, hitting well, showing off elite speed on the bases and in center field, and making one of the year’s most memorable defensive highlights with his arm. His top comps provide reason for skepticism, but PECOTA still thinks Laureano will be a top-15 center fielder in his first full season thanks to above-average work offensively, defensively, and on the bases. That would be an incredible rise for a 24-year-old perceived as a mid-level prospect when he was acquired from the Astros last offseason, but Laureano hit .297/.380/.524 at Triple-A before joining the A’s in August and his tools are loud enough to make it seem possible.

Jeff McNeil, New York Mets

Top Three Same-Age Comps: Jordany Valdespin, Rob Refsnyder, Justin Turner

McNeil’s remarkable transformation from high-average, low-power non-prospect to potential impact big-league bat began in 2017 and really took hold last season. First he convinced the BP prospect team that he was worth viewing in a new light, then he convinced the Mets, and now he’s convinced PECOTA. McNeil is already 27 and he’s without an obvious fit in the lineup, thanks in part to the Mets’ depth—as you may have noticed, they have three guys on this list—and in part to his defensive limitations, but the outfield may hold the key to regular at-bats. PECOTA thinks he’ll hit .280 with good strike-zone control and gap power, but if last year’s over-the-fence pop is for real … well, Jarrett Seidler will never shut up about it.

Tyler O’Neill, St. Louis Cardinals

Top Three Same-Age Comps: Paul Goldschmidt, George Springer, Chris Carter

O’Neill struck out a ton in the minors and BP’s prospect team has always viewed his long swing as a potential red flag, but PECOTA is infatuated with his power potential. O’Neill is projected for MLB’s ninth-highest isolated power, sandwiched between Khris Davis and Rhys Hoskins on the list, but PECOTA also sees him whiffing in 31 percent of his plate appearances while rarely walking. O’Neill looks like a bodybuilder and has plus speed, but plus defense may be a reach. He’s going to live or die on his ability to smack 35 homers. Acquired from the Mariners for Marco Gonzales two summers ago, O’Neill was as advertised in his first taste of the majors last season with nine homers and a 57/7 K/BB ratio in 142 plate appearances.

Franmil Reyes, San Diego Padres

Top Three Same-Age Comps: Jorge Soler, Wil Myers, Domonic Brown

Reyes is sort of the West Coast version of O’Neill (or maybe O’Neill is the Midwest version of Reyes): Big right-handed power, big strikeout rates, a promising small-sample MLB debut, and questions about the all-around skill set. Reyes has about seven inches and 75 pounds on O’Neill, making him less likely to be passable defensively in the outfield—the early numbers are hideous—but he also projects to have a better walk rate and his swing requires less effort to produce the tape-measure bombs. Reyes’ pre-2018 track record is also considerably less impressive than O’Neill’s, so let’s just agree to put them both in the “risky as hell” category while waiting to see whether PECOTA’s faith is justified.

Amed Rosario, New York Mets

Top Three Same-Age Comps: Orlando Arcia, Hanley Ramirez, Ketel Marte

PECOTA assigns Rosario the highest “breakout” rate (29 percent) of any hitter expected to be a regular this season, believing the 23-year-old former top-10 global prospect still has big-time upside. He had an uneven first full season with the Mets, rating below average at the plate and in the field among shortstops, but even relatively holding his own was somewhat impressive at 22. Rosario ranked among the 10 fastest runners in baseball and showed improved strike-zone control in August and September, which were his two best months. PECOTA sees him taking a small step up this season, but also recognizes the potential for 20-homer power and 30-steal speed if his development goes well.

Nick Senzel, Cincinnati Reds

Top Three Same-Age Comps: Vince Belnome, Ryan Rua, Devon Travis

One of four yet-to-debut prospects on this list because PECOTA projects them to make an immediate impact as rookies, Senzel moved up to Triple-A last season and hit .310/.378/.509, but the no. 2 overall pick in the 2016 draft was limited to 44 games by injuries. Cincinnati’s unexpected shift to win-now mode following a busy, aggressive offseason lines up perfectly with Senzel’s big-league readiness at age 24. His long-term home defensively is unclear, but it sounds like he could get a shot in center field initially as the Reds focus on simply getting his bat in the lineup somewhere. Assuming last year’s health issues don’t linger, PECOTA and the BP prospect team agree that Senzel is as safe a bet as a 23-year-old rookie can be.

Luke Voit, New York Yankees

Top Three Same-Age Comps: Nate Freiman, Steve Pearce, Jesus Aguilar

All but written off as a Quad-A slugger despite a grand total of 125 at-bats with the Cardinals, the 27-year-old Voit got an unexpected opportunity following a midseason trade to the Yankees and hit .333/.405/.689 in 39 games to fling open all kinds of doors. PECOTA projecting Voit as one of the 25 best hitters in baseball is a surprise, but he’s a career .314/.398/.532 hitter at Triple-A and was already on the radar enough to be the first baseman on my Quadruple-A All-Star team two years ago. Voit’s top comps are a mixed bag, which is to be expected for a 28-year-old with such little big-league experience, but stylistically Pearce and Aguilar seem like viable paths to follow for a solid career.

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