BOSTON — When T.J. Oshie got back to the bench 4:09 into the second period Thursday night, head athletic trainer Jason Serbus said something into Oshie’s ear that prompted the Capitals forward to stand and slam his stick in frustration as he made his way down the tunnel and to the locker room. Minutes earlier, Boston Bruins defenseman Kevan Miller hit Oshie into the glass and after crumpling to the ice, Oshie was slow to get up, appearing dazed.

He finished his shift and then played on the power play. But a concussion spotter watching the game had seen enough to tell Washington’s staff that Oshie warranted further examination, pulling him from the game, which Washington won, 4-2. For a third time this season, Oshie went through the concussion protocol before returning to the ice roughly 10 minutes later in the second period.

Oshie missed 11 games earlier this season with the fifth concussion of his career.

“I’ve been through that concussion protocol one more time than I’d like to,” he said. “When I felt fine and I was told I had to go, I understand it’s for the best, but in the heat of the moment, you don’t want to leave the game, especially having left the game a couple of times now this season. And I felt fine. I went and did all the testing, aced it and got back out there.”

The NHL added concussion spotters in 2016, and along with in-arena spotters, there are also spotters watching games on television in New York, authorized to require a player’s removal from the game if he shows visible signs of a possible concussion following a blow to the head. Clubs that do not remove a player who requires an evaluation are subject to a mandatory minimum fine for a first offense with increased fine amounts for subsequent offenses.

Oshie isn’t the first player to exhibit some frustration over a spotter making him leave the game. In December 2016, Edmonton Oilers center Connor McDavid said he was “pretty shocked” when he was pulled after he hit his chin on the ice. “Obviously the spotter thought he knew how I was feeling,” McDavid said at the time. Goaltender Mike Smith similarly complained two years ago.

In a physical game, Oshie wasn’t the only Capitals player who was placed in the concussion protocol. Defenseman Dmitry Orlov went down in the third period after colliding with Ryan Donato’s shoulder, and though Orlov didn’t return to the game, Coach Todd Reirden said he was cleared.

“It was a little scrappy out there,” Oshie said. “It had a little bit of a playoff feel which we have experience in and I think we like in here.”

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