Cespedes was pulled from Sunday's game against the Mariners after the third inning with a sprained left thumb, injuring himself when he slid into second on a successful stolen base attempt in the first inning. Jonny Gomes replaced him in left field.
"Literally day-to-day, not really sure how he's going to feel tomorrow," A's manager Bob Melvin said. "He's going to have four days off and hopefully after the four days, he's ready to go, but not really sure. Usually the next day you have a better indication of how he's feeling."
Melvin also said that while he couldn't be certain whether Cespedes might have to go on the 15-day disabled list, the team's medical staff doesn't currently think he will have to.
The rookie was noticeably bothered by his left hand when he was in the game, as he shook it several times in apparent discomfort before he was taken out.
Earlier this season, Cespedes spent 20 days on the 15-day DL with a strained muscle in his left hand. He then missed several games over the next couple of weeks after he was activated on June 1 due to a strained left hamstring.