Penguins forward Jayson Megna collided with Mason with 3:33 remaining in the second period. Mason took off his helmet, blocker and glove while he kneeled in the crease during a timeout.
He played the remainder of the second period before being replaced by Ray Emery to start the third. Emery stopped 12 of 14 shots in a 4-3 overtime win.
Flyers coach Craig Berube said he was not sure of the severity of Mason's injury but expects him to be prepared to start Game 1 of the Stanley Cup Playoffs against the New York Rangers in the Eastern Conference First Round.
He's only 17 but he can see the ice so well and he moves the puck and goes to the open ice all the time, so I just think he's a player that is ready to play in the NHL. I'm really looking forward to coaching someone like this.
— U.S. National Junior Team coach Ron Wilson on Auston Matthews, the projected No. 1 pick of the 2016 NHL Draft