Originally a third round draft pick out of high school, Derek Dietrich chose not to sign, instead attending the Georgia Institute of Technology. The Rays drafted him in the second round three years later, finally signing him to a $457,200 bonus.
The 6-foot-1 left-hander garnered attention in 2011 by batting .277/.346/.502 for the Bowling Green Hot Rods. He also hit 22 home runs, the most of any Rays prospect that year. Some evaluators expressed concern that Dietrich merely feasted on bad Class-A pitching, but he helped address those questions by putting up a .282/.343/.468 line in the Florida State League this past year. The Rays saw fit to promote him to Double-A, where held his own in 34 games, hitting .271/.324/.429. The Marlins will likely start him again in Double-A, with the expectation that he will move up to Triple-A mid-season. If Dietrich crushes the ball, he could be playing for the Marlins by the year's end.
Dietrich projects to be an average hitting third basemen or an above-average hitting second basemen, not unlike Washington Nationals second basemen Danny Espinosa. Neither player have strong on-base skills, but they do possess solid power for middle infielders. Dietrich's minor league numbers are mildly reminiscent of Espinosa's too. In his age 22 season, Espinosa put up a 134 wRC+ in high Class-A Potomac, just a bit higher than Dietrich's 128 wRC+ last season. While he will likely never match Espinosa's major league 7.8 percent walk rate, Dietrich strikes out less than Espinosa and hits for a higher average.
Unfortunately, Dietrich lacks Espinosa's prodigious athleticism and defensive abilities. He came up through the Rays system as a shortstop, but was later moved to second base to make room for prospect Hak-Ju Lee. Reports indicate that Dietrich is a below-average runner and doesn't display much range on defense. His arm and glove are said to be adequate. My feeling is that Dietrich would make an average defensive third basemen or a below-average defensive second basemen. I cannot make a definitive judgment until I see him play, however.
While the the front office's systematic dismantling of the major league roster has dramatically improved the farm system, the minor league talent is concentrated in the outfield, catching, and pitching. Prior to this trade, the only infield prospects to speak of were Zack Cox, Austin Barnes, and Noah Perio - all of whom come with serious question marks. Adeiny Hechavarria technically remains a prospect, but he will start at shortstop for the Marlins next year. The acquisition of Dietrich will partially resolve the franchise's lack of minor league infield depth, although the organization would be wise to seek additional infielders in the First-Year Player Draft.