He won't travel with the team Tuesday and he likely will be listed as day-to-day heading into Friday's home game against Philadelphia. Butler left Monday's game against Boston in the third quarter.
"We don't think it's serious," Mavericks coach Rick Carlisle said. "But, we want to get it taken care of.''
Third on the team in scoring at 14.2 points a game, Butler has gotten off to a rocky shooting start at just 39.1 percent from the field. In the last two games, he's made just 10-of-30 attempts.
Butler's absence will force Carlisle to use a different starting lineup for a second consecutive game. Against Boston, DeShawn Stevenson started at shooting guard to allow Jason Terry to provide offense off the bench.
Shawn Marion, who played the entire fourth quarter against Boston with Butler out, could get his first start after moving to the bench this season.