LAS VEGAS — William Karlsson had a goal and an assist in his season debut, and the Vegas Golden Knights handed the San Jose Sharks their ninth straight loss with a 7-3 win at T-Mobile Arena on Saturday.

Karlsson had missed the first eight games because of an undisclosed injury.

“He just does so many things throughout the game in all aspects. Special teams, 5-on-5,” Golden Knights defenseman Alex Pietrangelo said. “He’s an elite centerman. Especially an elite defensive centerman.”

Mark Stone and Pavel Dorofeyev each had a goal and two assists, Brett Howden scored twice, and Jack Eichel had a goal and an assist for Vegas (6-2-1), which was coming off a 6-4 win against the Ottawa Senators on Friday. Ilya Samsonov made 23 saves.

“We played well. [The first period] was our best probably single period of the season,” Golden Knights coach Bruce Cassidy said. “At the end of the day, they were ready to go. That’s our job as coaches to make sure they’re prepared. From there, the game took care of itself.”

Mikael Granlund, Nico Sturm and Luke Kunin scored, and Vitek Vanecek made 35 saves for San Jose (0-7-2).

“I don’t think anyone’s happy by any means. There are a lot of emotions in that locker room,” Sharks coach Ryan Warsofsky said. “Frustration, anger. It’s tough.”

Tanner Pearson gave Vegas a 1-0 lead at 1:57 of the first period with a one-timer from the left circle off a pass from Karlsson.

“It was easy to play [with Pearson],” Karlsson said. “It’s always nice to be on the same page. Even though we’ve never skated before, he was easy. That stood out.”

Eichel extended the lead to 2-0 at 3:47. Following a face-off win, Eichel skated into the left circle and scored short side with a one-timer off a diagonal cross-ice pass from Stone.

Howden made it 3-0 at 16:46, finishing a cross-ice pass from Tomas Hertl near the left post.

“Pucks are finding him in the slot,” Cassidy said. “He’s finishing some plays on good passes, but he still has to finish them. So far, that’s been good.”

Granlund cut the lead to 3-1 at 10:13 of the second period, jamming in the puck at the right post.

Karlsson pushed it to 4-1 at 11:10 with a short-handed goal. Vanecek came deep out of his crease to play the puck, but Karlsson won the footrace and poked it away from him. He then skated back up into the right circle and scored before Vanecek could get back into position.

“I felt it didn’t have too much mustard on it, and it stopped there,” Karlsson said. “I got there before their goalie. Just waited and waited. I wanted to hit [Pearson], but I didn’t feel like it. Then I just shot it. Luckily, it went in.”

Dorofeyev increased the lead to 5-1 with a power-play goal at 19:26.

Sturm scored 15 seconds later to make it 5-2.

Stone made it 6-2 at 11:10 of the third period, scoring from the left circle off a no-look pass from Eichel as he skated around the net.

Kunin cut it to 6-3 at 13:29, jamming in a rebound in the crease.

Howden scored his second of the game at 17:07 for the 7-3 final.

“We got to find a way to weather the storm in energetic buildings,” Sharks defenseman Mario Ferraro said. “We’re chasing the game far too much right now. There are a lot more reasons that we’re not good enough. That’s definitely something that’s not helping our cause.”

NOTES: Pietrangelo had two assists. He has eight assists during a three-game multipoint streak. … Hertl was playing his first game against the Sharks since being traded to the Golden Knights on March 8. He has seven points (three goals, four assists) in his past three games. … The Golden Knights have outscored their opponents 19-8 during a three-game winning streak. They also extended their season-opening home winning streak to six games.