Derek Dietrich has been the Marlins’ starting second baseman since being called up from the minors in the middle of last season and he’s actually hit well this year with a .773 OPS in 41 games, but he’s been demoted back to Triple-A because the team thinks his defense is terrible.
Dietrich has seven errors, which is tied for the MLB lead among second basemen, and Manny Navarro of the Miami Herald writes that he “has had plenty of defensive struggles” even beyond the error total. Ultimate Zone Rating agrees, pegging Dietrich as 9.0 runs below average in 800 career innings at the position.
But still: 24-year-old middle infielders with a .773 OPS don’t grow on trees and Dietrich’s defensive numbers aren’t considerably worse than plenty of other regulars with good bats. He’s a former Rays second-round draft pick who was acquired by the Marlins in exchange for Yunel Escobar and certainly seems good enough to remain in their long-term plans.