Brian Dumoulin said that the injury that kept him out of the final six games of the Penguins' playoff run was a grade 3 tear of his MCL.
Dumoulin, speaking with reporters during the Penguins' locker room cleanout day on Tuesday, said that he suffered the injury in Game 1 when he crashed into the Penguins' net when he collided with Filip Chytil on the Rangers' goal that was disallowed for goaltender interference:
Dumoulin said that his knee hit the post on the play, causing it to hyperextend, though he didn't feel the pain in the moment.