Castillo, Tomas lead group of must-watch Cuban rookies in 2015

Can Rusney Castillo and these Cuban rookies follow in the footsteps of countrymen Yasiel Puig and Jose Abreu to find MLB stardom?

On Friday, Cliff Corcoran and I ran through short lists of impact rookies on the pitching and position player sides, some of whom have already gotten tastes of major league action, others of whom are likely to make their debuts early enough this season to play significant roles. Excluded from those lists was a wave of promising new Cuban imports, all of whom are headed into their first full seasons in the United States. Relative to their stateside peers, they're more unknown commodities despite having upper-level professional experience in their homeland. Within this group might be this year's Jose Abreu, a potential Rookie-of-the-Year candidate—though there are no guarantees.

Note that these are players likely to see significant time at the major league level in 2015, meaning that record-setting 19-year-old Red Sox signee Yoan Moncada is not among them. The players are listed alphabetically.

Rusney Castillo, CF, Red Sox

Before Moncada was a twinkle in their eye, the Red Sox signed the 27-year-old Castillo to a record-setting seven-year, $72.5 million deal. Castillo ended up playing 11 minor league playoff games for the team's Rookie League, Double A and Triple A affiliates, hitting a combined .293/.370/.463 with one homer in 46 plate appearances. He then sparkled in 10 games at the major league level in late September (.333/.400/.528 with two homers in 40 PA) before adding another eight games in the Arizona Fall League and 10 in the Puerto Rico Winter League.

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Prior to coming to America, Castillo spent parts of five seasons with the Ciego de Avila Tigres in Cuba's Serie Nacional, hitting a combined .315/.380/.501 with big seasons in 2010-11 and 2011-12 but hitting just .274/.377/.393 with six homers and 15 steals in his final year before defecting in December 2013. He spent time as the regular centerfielder on the Cuban national team once Yoenis Cespedes and Leonys Martin defected, earning All-Star honors at the 2011 Baseball World Cup in Panama and playing in exhibitions with the national team in the run-up to the 2013 World Baseball Classic before being left off the final roster due to a suspension, apparently for trying to defect.

A high-energy combination of speed, power and plus defense in centerfield, the 5'8", 185-pound Castillo drew comparisons to Andrew McCutchen and prime Shane Victorino when he signed. He's considered to have 20-homer/20-steal potential, and the Sox brass views him as major league ready, which means that he's part of an outfield logjam that includes a pair of centerfielders who were rookies last year: light-hitting defensive whiz Jackie Bradley Jr. and converted second baseman Mookie Betts. It's unclear how all of it will shake out in the early going—particularly with Castillo nursing a minor oblique strain—but the contract and small-sample performance suggest that he'll be the starter before too long.

Raisel Iglesias, RHP, Reds

The Reds signed the 24-year-old Iglesias (25 on April 1) to a seven-year, $27 million contact last June, but until this spring, his stateside action was limited to the instructional league and the Arizona Fall League, where he was dominant in seven one-inning relief stints, allowing just one hit and whiffing seven. For Cuba, he spent three seasons in Serie Naiconal, posting a 3.47 ERA despite shaky walk and strikeout rates (4.6 and 6.8 per nine, respectively, though his 2012-13 numbers were 3.3 and 8.1). All but five of his 88 appearances came in a relief role. He also made tournament appearances for the national team, serving as a go-to reliever during the 2013 World Baseball Classic.

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Somehow, Iglesias has magically grown from 5'11" and 170 pounds when he signed to 6'2" and 185 pounds when added to the Reds' roster. Either way, he's considered on the small side for a pitcher, and prior to his signing, most teams viewed him as a reliever, though the Reds are working him as a starter this spring, much as they did with fellow Cuban Aroldis Chapman at one point. Iglesias doesn't have Chapman's heat, but in the AFL, he sat 92-95 mph and reached 97 in those short stints. He's got a plus slider, which he throws from a variety of arm angles to the point that it's sometimes seen as a hard curve, and a changeup that's relatively advanced given how little he's worked as a starter.

The Reds have more than enough candidates to fill out their rotation behind Johnny Cueto, Mike Leake and Homer Bailey (who's behind schedule due to flexor mass tendon surgery in September), but the most likely scenario has Iglesias opening the season in the bullpen, working toward a late-inning role.

Yoan Lopez, RHP, Diamondbacks

Like Moncada, and unlike the other three players here, Lopez's young age (21) and level of experience (three years in Serie Nacional) made him subject to international signing rules. So when the Diamondbacks inked him to an $8.27 million bonus in January (briefly a record), it carried a 100 percent tax for the team exceeding their spending pool, just as Boston did for Moncada.

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Pitching primarily as a starter for Isla de la Juventud, Lopez posted a 3.76 ERA during his three seasons, albeit with more walks than strikeouts—4.7 and 4.5 per nine overall, respectively, though at a more respectable 2.0 and 5.1 in the 49 innings he pitched during 2013-14 before defecting. Now 6'4" and 190 pounds, Lopez was clocked as high as 100 mph (three times) during his workouts for teams; his fastball generally sits in the 93-95 range, but his command needs refinement. His arsenal is augmented by a curve with the makings of a plus pitch, as well as a changeup that could become a solid third pitch, topped off by a cutter and a slider. MLB.com ranked him as the team's No. 6 prospect, adding, "There's a fair amount of projection with Lopez. With some time to harness his stuff, he could be a No. 3-type starter at the big league level in the very near future."

Ostensibly, Lopez is currently competing for a spot at the back of the Diamondbacks' wide-open rotation, where Josh Collmenter and Jeremy Hellickson are the only certainties. A broad cast of characters—Chase Anderson, Vidal Nuno, Trevor Cahill, Daniel Hudson, Rubby De La Rosa, Allen Webster, Robbie Ray, Randall Delgado and top prospect Archie Bradley—are also in the mix. Given that crowd, the likelihood is that Lopez starts the year in the minors, but he hasn't been ruled out of the running yet, even with a rough first spring start under his belt.

Yasmany Tomas, 3B/OF, Diamondbacks

In November, the Diamondbacks signed Tomas, a 24-year-old Cuban defector, to a six-year, $68.5 million deal. Prior to defecting, he spent five years playing for Industriales in Serie Nacional, hitting a combined .290/.345/.504 but trending downward in the power department; in 2013-14, he batted .290/.346/.450 with six homers in 257 PA. He starred for the national team in the 2013 World Baseball Classic, posting a 1.224 OPS with two homers. Listed at 6'2" and 230 pounds, Tomas drew one scout's comparison to Marlon Byrd as far as physique, which is to say that he's no Yasiel Puig. He's got a mechanically sound swing that should produce power in the 25-to-30 homer range, but there's concern that he won't produce a high on-base percentage, and scouts consider him a below-average runner.

With a glut of corner outfielders, the Diamondbacks are trying Tomas at third base, where he's less comfortable but does have some experience. While early reports were encouraging, his Cactus League debut at the hot corner featured one misplay as well as several throws that needed to be dug out of the dirt by the first baseman. General manager Dave Stewart has placed the priority on Tomas living up to expectations on the offensive side, saying that the team won't force the issue if the experiment isn't working.