Civale allowed two hits and threw 20 pitches in the scoreless inning. Yoan Moncada and Eloy Jimenez were retired on fly balls that were caught on the warning track in right field. Manager Terry Francona said Civale will have an MRI to determine the extent of the injury.
"I think he has felt it for a little bit," Francona said. "It was happening quick so I just told [the training staff] to take him and got another pitcher in there.''
Civale missed a month earlier this season because of a left glute injury. The right-hander returned June 21 and was making his fifth start since coming off the injured list.
Civale sprained the middle finger on his pitching hand last season and was out from June 21 to Sept. 7.
The Associated Press contributed to this report.