There is ZERO question of his readiness. It's about corner outfield and about not having a long pause immediately after he arrives. This person said Marte's performance at the plate right now is "through the roof." Marte has made several starts in left but the one Monday was his first.
"His first" in right field, presumably. If Marte's lack of experience at the corner outfield positions is holding him back right now, it's bizarre that the Pirates didn't have him play those positions earlier, since it shouldn't have taken them by surprise that their center fielder is playing pretty well. Also, the transition from center field to a corner should be trivial for a player with Marte's defensive gifts.
Kovacevic mentions another reason that makes more sense, which is that the Pirates don't want Marte to come up and then immediately run into the All-Star break. I'd expect to see Marte soon after play resumes next week.
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