"I was worried because I wasn't feeling my shoulder the day I was pitching," said Doubront.
Doubront thinks the cause of the injury was bumping his shoulder into his car while he was trying to get one of his kids into the back seat.
"I hit the car door getting in," Doubront said. "It was just something that happened. I hit it hard but I wasn't thinking of that. I came in the next day, I was feeling a little weird and the next day I was pitching. It's crazy, but thank God it's nothing major."
In a perfect world, Doubront will miss just two starts.
"He threw flat ground light catch today and he'll be in the early stages of that," said manager John Farrell. "That won't rapidly pick up, but the encouraging thing is there are no restrictions for the range of motion. He's nowhere near game speed obviously, so that will be the tell-tale sign. Once we get him back to the mound and start to ask him to increase the overall intensity, then we'll get a better read."
Ian Browne is a reporter for MLB.com. Read his blog, Brownie Points, and follow him on Twitter @IanMBrowne. This story was not subject to the approval of Major League Baseball or its clubs.