"It isn't one specific area that you have a strength deficit, even though he has overall fatigue," manager John Farrell said. "We saw that in the velocity last night. The exam didn't pinpoint one specific spot. The impact of the contusion didn't allow the shoulder to fire normally."
Doubront didn't tell anyone about the accident until after the game when he was examined by team physicians.
"If he felt it was that severe, he would have said something," Farrell said. "He didn't feel like it would hinder his ability to pitch."
The team isn't planning on sending Doubront for an MRI unless he doesn't respond to treatment.
Doubront is 2-4 with a 5.12 ERA in nine starts this season. Prior to Tuesday's outing, Doubront surrendered just one earned run in back-to-back contests.
Brandon Workman and Allen Webster are the likely candidates to replace Doubront in the rotation. Workman started three games for the Red Sox last season and pitched in three games out of the bullpen the first week of this season. Webster started seven games for Boston last season, going 1-2 with an 8.59 ERA.
"We have a group of pitchers who have already made their debut and have experience here, and they are talented," Farrell said.
Quinn Roberts is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.