A week after he was knocked out of playoff game with a concussion, Pittsburgh star Sidney Crosby slid headfirst into the boards during another tense game against the Washington Capitals.

He did not come out of Game 6 on Monday night.

Deputy Commissioner Bill Daly told The Associated Press in an email Tuesday that the league’s centralized concussion spotter decided the play did not meet concussion protocol criteria that require mandatory removal from play. The protocol states a player must be removed if a spotter sees symptoms in a player who takes a blow to his head or upper torso from another player’s shoulder, his head hitting the ice or from a punch to the head.

Crosby slid into the boards exactly one week after he was knocked out of Game 3 by a blow the head from the Capitals’ Matt Niskanen. He missed Game 4 with a concussion and returned for Game 5 on Saturday.

On Tuesday after practice, Crosby said he was checked by a doctor Monday night but did not go into concussion protocol.

“Any guy that goes into the boards like that, the first thing is the trainer and the doctors, that’s how it goes,” Crosby said. “What you’re talking about is the difference between checking with a doctor and entering concussion protocol, they’re two separate things.”

Penguins coach Mike Sullivan said after the 5-2 loss and again Tuesday that Crosby was not in the protocol.

“If they go through the protocol then I usually get notified by our medical staff, that’s the process,” Sullivan said. “That’s completely out of our control.”

The league added centralized spotters this season who have the authority to remove players if they see symptoms of a concussion, like the NFL. During the regular season, Edmonton Oilers center Connor McDavid expressed his displeasure for being pulled from a game by a spotter after his chin hit the ice, and goaltenders Mike Smith and Henrik Lundqvist criticized the system they consider flawed.

Daly said he can’t answer whether the league would consider adding hitting the boards to the list requiring mandatory removal from play. He said current criteria are based on a study that determined what events on the ice were “more likely indicators or predictors of (a) concussion.”