Penguins captain Sidney Crosby and forward Bryan Rust both left Saturday's preseason game against Buffalo after blocking shots.
"They are being evaluated now. We will probably have more definitive answers (Sunday) morning," said Penguins head coach Mike Sullivan.
Crosby left late in the first period and did not return. Rust left after blocking a shot with his hand in the third period and missed the remainder of the game.
The Penguins lost, 3-2, in a shootout to Buffalo.