CHICAGO -- Tim Wakefield woke up Friday feeling no worse for the wear from his side session a day earlier, and that was all Red Sox manager Terry Francona needed to officially line up the knuckleballer for a return to the rotation on Saturday afternoon against the White Sox.

Junichi Tazawa, the 23-year-old Japanese righty who made five starts for Boston, has been moved to the bullpen, essentially giving the Red Sox the long man they didn't really have previously

"[Tazawa] will be available tonight and available tomorrow, and it will give us a little bit more depth. We'll see how he does," said Francona.

As far as Wakefield is concerned, the Red Sox know that he won't be fully recovered from back woes until the root of the problem -- a loose fragment -- is surgically removed. The cortisone shot Wakefield had earlier this week has alleviated the pain enough that he thinks he can pitch.

"He threw the ball great [in the side session], which we all knew," Francona said. "We just wanted to see how he would bounce back. If he threw and came in this morning and said, 'Hey, you know what, this is not good,' we wouldn't do that. We know what we're dealing with."

When Wakefield initially returned from the disabled list and threw seven solid innings against the White Sox on Aug. 26, he had to miss his next start when his back locked up again a couple of days later.

"He might not be able to take the ball every five days or six. We know that," Francona said. "He knows that. But we'll just kind of see how he does."

With Paul Byrd back in the fold and Daisuke Matsuzaka soon to be activated, the Red Sox might be able to pick their spots with Wakefield down the stretch.

Francona isn't sure yet who will catch Wakefield on Saturday. George Kottaras has been his regular catcher for most of the season. But when Wakefield made his last start, Kottaras was on the disabled list and Victor Martinez did well with the knuckleball.

Once the White Sox settle on starters for Sunday and Monday, Francona will better be able to align his catching rotation for the rest of this weekend.

"I think George has done a great job," Francona said. "At the same time, you're looking at an All-Star catcher or an All-Star bat. We'll see. I don't know what to do yet, or what we're going to o just because I want to see what they're doing all four days."