Plouffe, who is on the disabled list retroactive to July 21, is eligible to return from the DL on Sunday. He originally injured his thumb when he was jammed by a pitch against the Royals on July 20.
"I don't know how comfortable he was swinging the bat [Thursday]," assistant general manager Rob Antony said. "I think there's still some soreness, but I would doubt he'll join us in Cleveland. That's uncertain, but probably not as optimistic as we were a day ago. Until he can swing without any pain in that thumb, I don't think he'll be rejoining us."
There's also a chance that Plouffe will go on a rehab assignment once he feels more comfortable swinging the bat without pain.