McCarthy will make a second rehab start for Sacramento on Saturday, barring any setbacks with his scheduled bullpen session on Thursday. McCarthy will then presumably rejoin the A's rotation at some point next week, though it's unclear how his presence will shake up the current roster.
Outfielder Coco Crisp (left hamstring) made "significant progress" on the field Wednesday, Melvin said, and he appears close to returning to the lineup. Crisp has missed four straight games.
Cliff Pennington, on the disabled list with left elbow tendinitis, will hit on the field Thursday before departing for Sacramento on Friday to begin a rehab stint with the River Cats.