Mountcastle went 2-for-3 with a double and a solo home run in Saturday's 10-4 loss to Cleveland.
The 24-year-old is locked in at the plate, going yard four times in the last five games as part of an 8-for-19 (.421) surge. On the season, Mountcastle is batting .245 with eight homers, three steals, 21 runs and 28 RBI through 53 contests.