"He went down to hit early today, and the soreness continues to persist and gain in intensity, so he's going to be heading back to Boston to get a work-up first thing in the morning," said Red Sox manager John Farrell.
The Red Sox won't know about Pedroia's availability for the three-game series in Chicago from Tuesday-Thursday until the results from that exam are known.
Pedroia hasn't looked like himself at the plate since suffering the injury, which he hadn't mentioned to the media before being taken out of Sunday's game.
Pedroia frequently plays through ailments without looking for excuses. Last season, he suffered a torn UCL in his left thumb on Opening Day and it didn't become public knowledge until late May.
Pedroia is 6-for-40 since April 4.
"There's probably a direct correlation to what we've seen at the plate," said Farrell. "There hasn't been an event over the past couple of days that has brought this onset even further. It's more just everyday play that the soreness increases. It's got to be checked out. Until we have some results of imaging of any kind, that's the best I can tell you."