Though the Red Sox haven't said publicly what Buchholz's ceiling is, it is believed to be somewhere around 160 innings.
"We're very careful to try to do things correctly," Francona said. "It's kind of been proven with young pitchers, if you increase their increments too much, you're putting them at unnecessary risk. We don't want to do that. We'd also like to win as many games as possible and go really deep into the year. So you try to mix and match both."
The Sox had held off on announcing their next plan with Buchholz until verifying that Tim Wakefield could return to the rotation on Thursday night in Baltimore. Wakefield cleared that hurdle by throwing a side session before Tuesday's game.
Wakefield missed his last start because of back stiffness, putting Buchholz in position to make the Saturday night start against the Orioles in which he threw the no-no.
"And what we'll do with Clay is try to get him on a structured innings [program] and out of the bullpen," said Francona. "That doesn't mean he won't start a game again. But because of organizational philosophy and caring about innings, developmental innings, Major League innings ... and again, we're not going to just state in advance, because we're trying to win games, there will be some structure in place."
Buchholz expressed no reservations about the new role.
"It's a role that I'm about to play for a little while," said Buchholz. "It's still pitching, it's just a little bit different. I think your demeanor has to be a little bit different, as far as coming out and not being able to go through the lineup full-time in the first inning and setting up guys to how you want them to be set up."
Francona wouldn't say specifically how Buchholz -- who made one relief appearance in the Minor Leagues this season -- will be used.
"Structured innings," Francona said. "Again, I don't think that in the middle of a pennant race I need to tell the other manager how we're going to do things, but I think that kind of speaks for itself."
Mirabelli will catch Wake: Backup catcher Doug Mirabelli, who has been sidelined since Aug. 17 with a strained right calf, is expected to be back in the lineup Thursday night to work with long-time batterymate Wakefield.
Mirabelli, who had been away from the team for a couple of days for a serious personal matter, caught Wakefield's bullpen session on Tuesday.
Manny keeps working: Francona remains unsure when slugger Manny Ramirez, sidelined since Aug. 29 with a strained left oblique, will be able to resume baseball activities.
"He's working the core area and doing some rotational [stuff] with the ball at a pretty crisp rate," Francona said. "There's some movement involved. I said it yesterday and I'll say it again today, he's really doing a good job of trying to get back on the field as quickly as he can. When that is, we don't know."
In other injury news, setup man Eric Gagne (tender right shoulder) played catch for the second day in a row and could be close to getting back on the mound.
Closing thoughts: The Red Sox went into Tuesday's game with the very real possibility that both Hideki Okajima and Jonathan Papelbon -- the team's top two relievers -- would be unavailable. Both men had worked on back-to-back days.
Francona chose to be coy on the matter.
"If you see a guy in a game, he's a available," Francona said. "If you don't, he wasn't. How's that? We need to use some proper caution with people. We'll be OK."
Hansack re-emerges: The Red Sox recalled right-hander Devern Hansack from Triple-A Pawtucket, officially closing the book on September callups.
Hansack, who has been used almost exclusively as a starter at Pawtucket, will be available out of the bullpen for Boston.
"We don't know how many innings are there, but we'd like to see how that role fits him, again, looking down the road," Francona said.
Coming up: Right-hander Curt Schilling (8-6, 4.02 ERA) will close out this three-game series against the Blue Jays when he's opposed by right-hander Shaun Marcum on Wednesday night. First pitch is scheduled for 7:05 p.m. ET.