Benn was injured in a second period collision with Flames defenseman Mark Giordano, whose skate appeared to catch Benn in the thigh.
"He's got a cut on his leg. He got hit by a skate. He's got stitches in his leg and he's going to be day-to-day," said Stars coach Glen Gulutzan. "It's a pretty decent size cut, so he is going to be day-to-day. He probably won't play in Phoenix (Saturday), but there is a possibility he could play here (vs. Nashville) on Sunday."
Benn is the Stars' leading scorer with 49 points (17 goals, 32 assists) in 52 games.