Joe Pavelski will move from right wing on the first line to center on the third line for Thornton, who was suspended for an illegal check to the head of Golden Knights forward Tomas Nosek in Game 3.
Vegas has won back-to-back games by a combined score of 11-6 and leads the best-of-7 series 2-1.
RELATED: [Complete Sharks vs. Golden Knights series coverage]
Thornton declined to comment, other than to say he felt good, it was tough to sit out and the team would be fine without him.
"Great player, big part of our team, but that's what you have to deal with," coach Peter DeBoer said. "You have no choice. I mean, you either feel sorry for yourself and mail it in, or you rally around it. I think that's the type of group we have."
With forward Micheal Haley day to day with a leg injury sustained in Game 3, forwards Joonas Donskoi and Lukas Radil will play for the first time in the series. Donskoi hasn't scored a goal in his past 34 games, but his last goal was the winner in a 3-2 victory against Vegas at T-Mobile Arena on Jan. 10.
"I'm excited to see them," DeBoer said. "Tough decisions sitting those guys out and putting our lineup in with what they've done and how good of players they are. I think [they need to] bring energy, bring excitement to our group like I know they're capable of."
At the morning skate, Logan Couture centered Timo Meier and Kevin Labanc, Tomas Hertl centered Evander Kane and Donskoi, and Pavelski centered Marcus Sorensen and Gustav Nyquist.
"Marcus, obviously he works," Pavelski said. "He's been a player that's just hungry on pucks, and he's shown that. He's crafty in tight areas. He doesn't mind playing a tight-area, physical game. [Nyquist] is a smart player. He's had the puck a lot. He makes a lot of plays.
"So if we can get in there, get some speed going, hopefully get rolling around a little bit and kind of take a few pucks to the net … We need to control play though, I think, and have that [offensive]-zone time and spend a little bit more time in their end, and hopefully we can get that."
Barclay Goodrow centered Radil and Melker Karlsson on the fourth line.
"Obviously a few lines shuffle," Pavelski said. "Throughout the year, we've seen different combinations at times, and we'll be fine."
Defenseman Marc-Edouard Vlasic has not skated with the Sharks since he left Game 2 after being struck by a shot.
