I think Martin will be headed back to St. Paul after the Yankee series, barring a disabling injury for a current Twins player and I think the demotion is fair, if not deserved.
At the plate, Martin has performed pretty much as expected—good contact skills, little power. The batting average and OBP are low, but for essentially a maiden voyage in the majors, he’s done okay.
Defensively, Martin has divided his time between left and center field, with just a cameo at second base. From what I’ve seen, the results are disappointing and I missed seeing the game last night and the one on Easter Sunday—two games where Martin’s play in the OF was panned.
Teams have taken extra bases on Martin’s arm and he’s made that problem worse by throwing to the wrong base. His route running has been at best adequate.
Austin has good speed and has been able to easily swipe bases, but from my observation that good speed hasn’t converted to great range in the outfield.
Martin has played about twice as many minor league innings in the infield, but it does seem like opportunity with the Twins is in the outfield. If he wants to thrive, he needs to be a much better defensive outfielder and perhaps he will make better decisions with more experience, but it doesn’t make his arm an asset.
So far, Martin looks like a marginal player with minimal upside. Unless his assets (base running, OBP) become elite or he improves his outfield defense significantly, his role in the majors will remain limited (IMHO obviously).