"He's improving upon things we've asked him to improve upon: walk-to-strikeout ratio, swing and chase, aggressivenes on bases, stealing bases, getting good leads. You did see him struggle in right field in spring training, so we're finding ways to get him more games on the corners (at Indy)."
The Pirates know more about Marte's development than outside commentators do, but their reluctance to promote Marte doesn't appear to make a whole lot of sense at this point. In particular, the idea that the Bucs can't promote him right now because of his lack of experience at corner outfield is nonsensical. It isn't as if the Pirates didn't know a year or two ago that they already had a pretty good center fielder, and yet they're just now starting to play Marte in right field in Indianapolis. Also, they're currently starting Drew Sutton, who plainly cannot play corner outfield, on a semi-regular basis. And the move from center to right really shouldn't be a serious issue for a player with Marte's defensive gifts.
Marte's strike-zone issues are very real concerns, but he's made strides there since last year. It's possible that the Pirates feel that he isn't as far along as he might be in that area, and at some point, you just have to trust them. Still, waiting is getting frustrating. Continuing to play Sutton in a corner is likely to cost the Pirates games in the end.
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