Baxter was called up from Triple-A Iowa on Tuesday, Carrie Muskat of MLB.com reports. A roster spot opened up when the Cubs traded catcher Welington Castillo to the Mariners, and the 30-year-old Baxter will be up to occupy that spot at least temporarily. Baxter has hit .290 with a .377 OBP in 34 games with Iowa this season, albeit with very little power (four doubles, zero homers). He will likely be used primarily as a pinch-hitter during his time with the big club.