Austin Dean
Austin Dean has the inside track for a roster spot, either as a starter in left field or as a bench player. Dean absolutely demolished high-level minor league pitching through the first four months of the season, slashing .345/.410/.511 in 109 games between the Jacksonville Jumbo Shrimp in the double-A Southern League and the triple-A New Orleans Baby Cakes in the Pacific Coast League.
In 34 games for the Miami Marlins, Dean hit just .221 with four home runs and 14 RBI. Despite that slight loss of sheen to his star, he’s got nothing left to prove in the minors, and can, at a minimum, produce at or above replacement level.
Monte Harrison
Monte Harrison is certainly exciting. Coming to the Miami Marlins along with Brinson, Isan Diaz, and Jordan Yamamoto for Christian Yelich, he showed us why.
Harrison led the Jumbo Shrimp by appearing in 136 games last season, and hit 19 homers while stealing 28 bases. He hit .240/.316/.399 with some truly tape-measure shots, but ended up leading the SL with 215 strikeouts in just 583 plate appearances.
The resultant 36.9 percent whiff rate was a truly frightening number. Maybe Harrison can fix the hole in his swing with another year of minor-league seasoning. For now, though, we can watch him get a shot against major league-hopeful pitching over the next several weeks.
Rosell Herrera
Rosell Herrera has hit .234 in 86 major league games through his career, all last season between the Cincinnati Reds and the Kansas City Royals.
Although he hasn’t shown a lot of power lately, he clubbed 16 round-trippers in 2013 with the full-season Asheville Tourists in the South Atlantic League. He’s also quite the modular player, and has appeared at every position on the diamond excepting catcher and first base over the past two seasons.
Magneuris Sierra
Magneuris Sierra is very fast. StatCast has clocked him going from home to first at a 30.2 ft/s sprint speed, the fastest time in the National League. Aside from that, there are a few questions.
Sierra hit just .190/.222/.211 for the Miami Marlins in 54 contests last season, drawing just six walks in 156 PA for a 3.85 percent walk rate. Not ideal for a speed guy you want at the top of the lineup. He also struck out 39 times, a full quarter of his plate appearances. Defensively, he fielded at a .962 percentage with four errors and four assists in 98 total chances.
Sierra has been touted as a high-floor guy, but landed below that in his short look in 2018. His 1.7 wins below replacement level was the lowest mark on the Miami Marlins, but he can do better. He’s going to need to if he wants to continue getting reps at the top level.
Curtis Granderson
The Grandy Man is well respected across baseball due to his excellent track record in engaging his surrounding communities. He’s also equally well respected on the ballfield.
Curtis Granderson‘s now 15-season major league career has seen him club 332 homers and collect 903 RBI. Now at the age of 37 (38 by the time the season starts), it may surprise some that his metrics have yet to fall off with his advancing age. His OPS+ hasn’t been below 100 since 2013, and it was only 99 that season. That was his lowest mark since 2006, when he scored a 98. His career mark is 114 in that metric, and he topped that in 2018 with a mark of 115.
Grandson has accomplished this despite losing the edge off of his power stroke by being more selective at the plate. As his slugging percentage has trended slowly downward, his OBP is climbing correspondingly. Still, he smacked 13 home runs last season in 403 plate appearances, so we know he can still get it done.