The move was designed to give ace Trevor Cahill an extra day of rest after starting Sunday against the Rangers, and to give Rich Harden some extra time before his next start. Cahill and Harden will start Saturday's doubleheader against the Angels, and Gio Gonzalez, the A's lone All-Star representative, will start Sunday.
Melvin said he was still unsure of the A's fifth starter coming out of the break. The A's have two off-days on June 18 and 21, so they could go with four starters until a fifth one is needed.
Melvin did say he wants to make sure Cahill gets two starts with an extra day's, rest and he also wants to be careful with Harden, thus the decision to bring McCarthy back first after the break.
"It will be hot today [in Texas]," Melvin said. "You want to make sure when [Cahill] comes back he's able to play catch the next day and therefore I gave him an extra day and then with the off-day that's two starts with an extra day."
Harden hasn't thrown 100 pitches yet through the first half, and with his injury history, Melvin also wants to play it safe.
"I want to make sure he's fully rested when he goes out there to pitch," Melvin said.