Dumoulin was injured during his first shift in Pittsburgh's 5-2 loss to the St. Louis Blues at Enterprise Center on Saturday. He got tangled up with Blues forward Zach Sanford, who fell on his left leg. Dumoulin had to be helped down the tunnel to the locker room and did not return.
The 28-year-old has seven points (one goal, six assists) in 23 games this season, averaging 21:04 of ice time, and is fourth in the NHL with a plus-17 rating.
The Penguins, who are also without center Sidney Crosby (core muscle surgery), forwards Nick Bjugstad (core muscle surgery) and Bryan Rust (lower body), and defenseman Justin Schultz (lower body), are off until they host the Blues at PPG Paints Arena on Wednesday (8 p.m. ET; NBCSN).
