"He's a little bit black and blue in his knee, which means there's a little bit of bleeding," said Red Sox manager Terry Francona. "Saying that, he feels pretty good. He has pretty good range of motion. I think he was doing some work in [the trainers room] and it kind of spasmed up on him. We have multiple off-days coming up. At least it gives us an opportunity -- we can wait. We've already talked to [Tim Wakefield] a little bit about possibly what the week looks like.
"But we'll go back [Monday] and I'm sure tonight a little bit, too, and talk to [general manager] Theo [Epstein] a little bit, and see how everybody is feeling. Kind of get our week in order. But we have some flexibility, which is great."
The way the rotation falls, Buchholz's regularly scheduled turn would be Saturday at Fenway Park against the Orioles. But Jon Lester would be rested enough to make that start if need be, and John Lackey could pitch Sunday, with Daisuke Matsuzaka taking the ball on July 5 against the Rays. If Buchholz requires extra rest, the Red Sox could actually wait until July 6 before they need a fifth starter in the rotation.
"At this point, his knee is good, but he's got a lower hamstring so it's kind of up to how he feels," Francona said.
Buchholz leads Boston's rotation in wins (10) and ERA (2.45).