This doesn't really fix much of anything at the big-league level, though I'm not sure it's intended to. Sutton plays mostly second and third and has a .724 OPS this year, although he's had higher ones at Class AAA in the past. We'll see if we end up seeing Sutton in the majors.
I thought this might have something to do with Jordy Mercer's injury, but Mercer played today. In any case, I'll assume this is a minor-league move, not anything meant to address the Pirates' offensive struggles at the major-league level. It certainly could help the Indianapolis offense a bit, for whatever that's worth.
In any case, the Pirates' real motivations aren't yet clear to me. Sutton's full name is Stephen Drew Sutton, so perhaps the Pirates are just confused. Alas, the real Stephen Drew -- who would, in fact, be quite helpful, if he were healthy -- is injured.