LAS VEGAS — The Vegas Golden Knights will be without one of their most important players as they try to stop the Carolina Hurricanes from lifting the Stanley Cup on Sunday night.

Center William Karlsson was ruled out for Game 6 by coach John Tortorella, who declined to address Karlsson’s status for a possible Game 7 should Vegas force one.

Karlsson took a hard hit from Carolina defenseman Sean Walker in the second period of their 4-2 Game 5 loss. After a trainer examined his left arm, Karlsson left the ice. ESPN’s Emily Kaplan reported that Karlsson left the arena for evaluation and did not return to the game.

Karlsson is a vital player to the Golden Knights in several ways. He has played on the Golden Knights’ power play and their penalty kill and was a key linemate for Mitch Marner, who leads the playoffs with 29 points. Karlsson has nine points in 15 playoff games, skating to a plus-10.

“It’s obviously a big miss,” said Marner on Saturday after the Knights’ morning skate. “He’s done a lot of great things for us since he’s been back. But we’ve done this all year. We’ve had a lot of injuries throughout the year, throughout playoffs. So obviously it sucks losing Will, but it’s a ‘next-man-up’ mentality.”

Teammate Tomas Hertl said he considers Karlsson an “underrated” player in the NHL.

“He’s such a good offensive and defensive player. He’s a great skater, good on faceoffs,” he said. “It’s obviously tough to replace him. But same time, this is a really good hockey team. There’s a lot of guys waiting for opportunity.”

Karlsson is one of a handful of “Golden Misfits” left from Vegas’ inaugural roster from its 2017-18 expansion season. Vegas was 7-3-4 in the regular season and 10-5 in the playoffs with Karlsson in the lineup.

“Obviously, a very tough blow on the ice, but off the ice as well,” defenseman Rasmus Andersson said. “But it’s this time of the year where other people have got to step up. He’s not someone you can replace. It’s got to be a group effort.”

Among the possible replacements in the lineup are veteran forward Brandon Saad, who has two assists in five playoff games and won two Stanley Cups with the Chicago Blackhawks, and forward Reilly Smith, who had two assists in six playoff games. Smith is a fellow “Golden Misfit” who was a member of the Knights’ 2023 Stanley Cup winner.

As for Marner, the loss of Karlsson could mean a move back to center, where he played a good portion of the regular season.

“We’ll see how it goes,” Marner said. “I think centerwise, you just got to be a little more patient defensively wise and with being in the right spot.”

The Stanley Cup will be in the building Sunday night. Tortorella vowed after their Game 5 loss that the Knights will be back in Raleigh for Game 7, going as far as to say he was leaving his clothes in the hotel there. That bravado wasn’t lost on his players.

“It’s the mindset we have. We’re going to do it the hard way now and that’s all we’ve done this year,” defenseman Brayden McNabb said. “We’ve had so much adversity this year. It’s another step in the road. So, it’s exciting. We can’t wait to get going.”