Gabriel Castellanos’ 2018 Season Review: Miami Marlins

Gabriel Enrique Castellanos  is a 6’1″, 165 lb. left-handed pitcher from Santo Domingo, Dominican Republic.

Throughout the 2018/2019 offseason, Marlin Maniac will devote one article each for every player who appeared in the Miami Marlins system for the 2018 season. Every. Single. Player. This is Part 173 of 286. For the first 100, click here.

Born on December 28th, 1993, Gabriel Castellanos signed with the Miami Marlins through international free agency during the 2010 signing period. After reporting to the rookie-level DSL Marlins in the Dominican Summer League in 2011, he posted an 0-4 record and a 10.20 ERA. He struck out five and walked 15 in 15 innings, and also gave up 17 base hits for a 2.13 WHIP.

In 2012, Castellanos remained with the DSL Marlins for another season of work, making six starts and coming out of the bullpen nine other times. In 43 2/3 innings, he struck out 37 and allowed a WHIP of 1.85 with a 5.98 ERA.

It was enough for him to join the GCL Marlins in the Gulf Coast League in 2013, where he entered the rotation and made a dozen starts. He went 3-4 and dropped his ERA down to 3.45 with 56 K’s in 47 innings. He also racked up what is still a career best WHIP of 1.26.

Castellanos split his next three seasons between the single-A Greensboro Grasshoppers and the short-season-A Batavia Muckdogs, in the South Atlantic League and the New York-Penn League, respectively.

In his season-and-a-half with Batavia, Castellanos struck out 92 in 98 innings, putting up a 4.87 ERA and a 1.50 WHIP while going 3-9. In 19 contests for Greensboro, including 17 starts, he whiffed 65 in 82 1/3 innings.

On June 24th, 2015, Castellanos struck out 12 Mahoning Valley Scrappers in seven perfect innings, then watched as Brett Lilek and Steven Farnworth finished the job for a combination perfect game.

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Castellanos entered the 2015 campaign as the Miami Marlins number 30 prospect, and it was the only time that he was ranked. From June 8th, 2016 through June 12th, 2018, he did not appear in a game, as he underwent Tommy John Surgery.

In 20 games for the Grasshoppers in 2018, all in relief, Castellanos allowed a .317/.430/.413 slashline over 131 plate appearances. He was 1-2 with a 7.71 ERA and a 1.870 WHIP during that time, but still struck out batters at an impressive 9.5 K/9 rate. He had his best game of the season on July 7th, when he issued two whiffs in 1 2/3 perfect innings in a 5-0 loss to the Lexington Legends.

On November 2nd, Castellanos was granted free agency, and is now free to sign with any organization, major league or otherwise.

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