Tom Wilson is helped off the ice by teammates John Carlson and Chandler Stephenson after suffering an apparent head injury Tuesday in Las Vegas. (Stephen R. Sylvanie/USA Today)

LAS VEGAS — Vegas Golden Knights forward Ryan Reaves slammed into an unsuspecting Tom Wilson in the second period of Tuesday night’s game, and the force of the check caused the Washington Capitals forward’s helmet to pop off, with Wilson then hitting his head on the ice as he fell to the ground. Wilson had to be helped to the Capitals' bench by two teammates, and he was unsteady on his feet even as he tried to make his way down the tunnel to the team’s locker room. He was ruled out for the rest of the game with what’s believed to be a concussion.

Coach Todd Reirden said Wilson will travel with the team for its remaining two games on this road trip, but he didn’t have an update on Wilson’s condition beyond that.

“Reaves targeted him the entire game,” Reirden said. “You could hear it on every faceoff. You could hear the things that were being said. It’s a blindside hit where an unsuspecting player hits his head on the ice. That’s disappointing. You could put two and two together, but he targeted him the entire game, so you can figure that out from there.”

Reaves was assessed a five-minute major for interference as well as a game misconduct and was ejected, and the late, blindside hit renewed the Capitals' occasional frustration with the NHL Department of Player Safety. That body decided Wednesday that Reaves would get no supplemental discipline for the hit.

Players didn’t call for Reaves to be suspended, but they also expressed confusion over what’s a legal check and what’s an illegal one, indicating the department has been inconsistent. Wilson has been suspended four times, the last of which caused him to miss the first 16 games of the season, and as Washington has had three players go down with concussions in the past month, there hasn’t been a suspension doled out in any of those episodes.

While the hit from Reaves on Wilson was certainly late and worthy of the infractions assessed on the ice, Reaves made contact with Wilson’s shoulder, not his head, and interference is rarely deemed suspension-worthy without head contact. Wilson’s head injury was caused by contact with the ice, not Reaves himself. It was not unlike an incident involving Wilson two games ago, when his hit on New Jersey Devils forward Brett Seney caused him to be ejected from the game. The check was ultimately not deemed suspension-worthy because, while it was late, the primary contact was through Seney’s shoulder.

“Who knows? Who knows anymore? I don’t think anyone knows what’s going on anymore, so we’ll see,” Capitals forward Brett Connolly said after Tuesday’s game, a 5-3 loss for Washington. “It goes both ways. Obviously, there’s hits that we’ve made, some guys on our team, that have resulted the other way. But it has to be consistent, or there’s no way the players are knowing what’s right and wrong. We’re trying our hardest as players to understand it. It’s still a physical game. There’s going to be hits. It’s just a matter of trying to figure it out and know what’s going on. But it’s a tough call.”

Just three weeks ago, Capitals forwards Evgeny Kuznetsov and T.J. Oshie both suffered concussions in the same game against the Winnipeg Jets. Kuznetsov was clipped in the head by defenseman Brandon Tanev, who was penalized for an illegal check to the head on the ice, but the Department of Player Safety didn’t suspend Tanev because Kuznetsov changed his position before the hit, which was believed to contribute to the contact. Josh Morrissey’s body slam of Oshie warranted a fine for unsportsmanlike conduct, but a similar play between Vancouver’s Elias Pettersson and Florida’s Mike Matheson led to a two-game suspension for Matheson. The differences in the two plays were that the puck wasn’t in the area when Matheson tossed Pettersson down to the ice and that hit had more of a retaliatory element to it.

It was Oshie’s fifth career concussion, and while he is not on this road trip with the Capitals, he has started to skate back in Washington, an encouraging sign after he missed the past nine games. Kuznetsov missed six games before returning to the lineup on Friday night.

With Oshie out, an injury to Wilson would leave the Capitals without their two top right wings. Going into Tuesday’s game, Wilson had scored eight goals with six assists in his first 10 games back from his suspension, playing on the top line and both special teams units. His return to the lineup had boosted the Capitals, who won eight of those 10 games.

“I don’t think any of us in here have any clue what the player safety department bases anything off of anymore, so that’s something that’s completely out of our hands,” goaltender Braden Holtby said Tuesday. “You know, that’s hockey. I think there’s been a lot of complaining about that stuff. We grew up loving a game that’s hard-nosed and you have to be tough to play it. I think that’s how Tom plays as well. That’s hockey. … It was a physical game, and I wish we’d see more games like that. Unfortunately with the player safety department, it’s taken away from that.”

Said Reirden: “That’s something I don’t really want to get into. I think we’re at point where that’s not a good thing, when players are feeling that way. I know that’s something we’ve got to figure out, but to comment any further, I think the league is working on it. It’s definitely not in a perfect spot right now because there’s a lot of situations that can be conflicting either way.”