McCarthy, who was forced to push back a start earlier this season with shoulder discomfort, was placed on the disabled list Sunday in a move that is retroactive to May 18.
McCarthy's last two starts since his start was pushed back have been pretty solid. He pitched seven innings of shutout ball, striking out 10 and not walking a batter on May 12. In his following start on May 17, he threw 5.1 innings and allowed four earned runs.
He has certainly been effective this year, taking the reigns as the A's No. 1 starter. He is 3-3 with a 2.95 ERA this season, and he's 3-0 with a 2.43 ERA over his last four starts.
This will be a challenge for the A's as they try to remain close to the Texas Rangers in the AL West. With an offense that often struggles, Oakland has to be able to rely on their pitching staff.
It is imperative that the rest of the staff picks up the slack while McCarthy is sidelined.