Dealing with a sports hernia injury that will require surgery at season's end, Youkilis has been back in the lineup for three games, going 1-for-9.
"He's sore," said manager Terry Francona, said after the Red Sox's 9-2 loss to the Rays on Thursday. "He's not going to play tomorrow for sure. I actually talked to him before the game a little and had a good talk. We'll watch him. He's nowhere near pulling the plug on the season or anything like that, but it's pretty obvious he's struggling out there. We'll see. I don't know exactly how to answer that, because I don't know what the answer is."
Youkilis hopes that on most days, he'll be able to grind through the pain.
"When you're injured, things are just not easy to do -- there's restrictions," Youkilis said. "I can't play at the elite level I want to play at at times. There are things you can do. You can get on base, get hits, drive the ball. You can do stuff to win. I'm not going to be stealing bases or going first to home probably on a lot of balls. The running is probably not going to be 100 percent 'till next year."
In most cases, Jed Lowrie plays third when Youkilis is out of the lineup. But Lowrie is also too sore to play because of ongoing problems with his left shoulder.
Mike Aviles is a likely candidate to start at third on Friday.