There is no structural damage, and no reason to think Beckett will need much more than the 15-day disabled list before reclaiming his spot in the rotation.
When the Red Sox scratched Beckett from his start Sunday against the Cubs, the reason was inflammation and some reduced strength from where he was earlier in the season.
That's something that should be able to be fixed with a little downtime and rehab.
Beckett is eligible to pitch for the Red Sox again on June 27. He indicated he will likely return within a couple days of that.
"We did an MRI yesterday and everything looks pretty good," Beckett said. "We took the steps necessary. I think we'll miss [one more] start and maybe push me back a day [in the rotation]."
Franklin Morales, who notched a career-high nine strikeouts over just five innings in Beckett's place at Wrigley Field, will take the ball again on Saturday against the Braves.
"I just had some pain that I was dealing with in my shoulder," said Beckett. "It's stuff that I've dealt with before. But whenever it starts taking away from strength, that's kind of where we've got to [get it checked], and the trainers made the decision that they made."
Beckett would have preferred to just be pushed back a day or two in the rotation instead of going on the DL. But he can see where the team is coming from.
"I kind of got overruled," Beckett said. "I told [manager] Bobby [Valentine] I thought I could make two more starts, then probably do the things that we did yesterday. But like I said, I got overruled. It was probably smart. I'm definitely not ready for my career to be over. That's kind of ... when you start getting inflammation plus strength limitations [and keep pitching], that's when you tend to do something catastrophic."