Rangers right wing Lee Stempniak has tested positive for mumps, the team said Monday. He has been isolated since Thursday.
Stempniak, the third Ranger to come down with mumps, skated on his own Monday, the team's off day, and is expected to practice with the team Tuesday.
Tanner Glass and Derick Brassard have recovered from mumps and have returned to the lineup, but it is unclear whether Stempniak, who has missed two games, will return against the Capitals at Madison Square Garden Tuesday night.
The Penguins, who have been among the hardest-hit NHL teams, sent forwards Steve Downie and Brandon Sutter and backup goaltender Thomas Greiss to Pittsburgh Monday to be tested, according to Penguins general manager Jim Rutherford.
The trio accompanied the team on its road trip to Florida Monday, he said, but will be placed in isolation until test results are known.