Calhoun (hamstring) began a rehab assignment at Triple-A Reno on Monday, Nick Piecoro of the Arizona Republic reports.
Calhoun, who started in right field, kicked off the rehab in grand style, smacking a pair of home runs in three at-bats before he was removed after five innings. He followed up with a second start Tuesday but was removed after getting hit by a pitch during his second plate appearance. It's unclear if the removal from Tuesday's game was precautionary or necessary.