Birthday: August 12th, 1988
Hometown/School: Santo Domingo, Dominican Republic
Marinez was signed by the Marlins as a amateur free agent back in 2006 and spent the next six years with the organization. He was acquired by the White Sox as compensation from the Marlins for Ozzie Guillen.
Marinez's greatest asset is his fastball which is in the mid-90s and it also has nice movement according to scouts. Baseball America named it the best fastball in the Marlins system in 2010 and 2011. In 2011, he earned a trip to play in the Futures Game.
As with a lot of big fastball pitchers, Marinez has had a history of control issues. In 2011, he was walking 6.5 batters per 9 innings. His control improved last year (4.3 BB/9), but his strikeout rate declined.
Marinez appeared in a pair of games late in the season last year for the White Sox (2.2 IP, 0 ER, 2 H, 2 BB, 1 K).
Below are a couple other scouting reports (they are from last year and haven't been updated for this year yet).
A Dominican who will probably be most-remembered for being one of the prospects traded for new Miami manager Ozzie Guillen, Jhan Marinez is a bit of an under-the-radar sleeper prospect now in the White Sox system who doesn't get as much attention as he probably deserves, despite his appearance in the Futures Game last season. Marinez is a slight player with a power fastball that can touch 98, but he has more success with his two-seamer, a 92mph offering with exceptional movement. His change and slider still need to improve before they're ready for the big stage, but he has so much raw talent that he's bound to make it sooner or later.
Marinez is your typical White Sox pitcher in the sense that he’s a hard thrower… but doesn’t always know where the ball is going. He had a breakout season in 2010 but took a step back in ’11 when his control deserted him and he posted a walk rate of 6.52 BB/9. He has the potential to be an eighth-inning stalwart.
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