Thornton scored the go-ahead goal with 8:36 left and added two assists to help the Sharks win their third straight, 3-2 over the Dallas Stars on Wednesday night.
"Milan made a great play and I slapped it in," said Thornton, who had a cut on the bridge of his nose caused by a teammate's stick in the first period. "He got it and he saw me and I don't think Marty had the time to react."
Thornton has figured in 10 of the Sharks' 11 goals in the last four games.
"It was a pretty dominating performance by Thornton," Sharks coach Ron Wilson said. "It's not just points but all the other little details he has in his game. To have a player like that, it's enjoyable to watch."
Patrick Marleau added a goal, Jonathan Cheechoo scored on the power play and Evgeni Nabokov stopped 17 shots for the Sharks, 7-1-3 in their last 11 games to pull within two points of the first-place Stars in the Pacific Division.
But the best player on the ice was Thornton.
"Thornton was the difference in the game," Stars coach Dave Tippett said.
Said Stars defensive forward Stu Barnes: "Joe Thornton is one of the best in the league. He has great hands, great vision and has a heavy shot. He's an outstanding player who had a great game."
U.S.-born goal-scoring leader Mike Modano notched the 516th of his career and defenseman Trevor Daley added his first of the season and ninth of his career for the Stars, opening a four-game homestand after going 4-2 on an East Coast trip.
Turco made 25 saves for the Stars, who had won eight of their previous 10.
Dallas held a two-man advantage for 47 seconds with less than three minutes left, but the Stars couldn't get a shot on net and saw their four-game home winning streak end.
"It did ratchet up the tension," Wilson said. "If they happen to score quick, then we've got another power play to kill."
Cheechoo got the game's first goal at 18:15 of the opening period, notching his fourth when he banked the puck off the stick of Dallas defenseman Niklas Grossman and past Turco while Stars defenseman Mattias Norstrom was in the penalty box for holding.
Cheechoo has been slumping this season after scoring 37 goals in 2006-07.
Daley tied it at 3:31 of the second period, taking the puck the length of the ice and beating Nabokov from the right circle.
Marleau put the Sharks back in front 2-1 with his fifth of the season at 6:02 of the second period, striking from the slot off Thornton's setup.
But Modano tied it at 2 on a sharp-angle shot at 6:08 of the third period, his ninth of the season.
"I thought we did a good job hanging around the game," Tippett said. "It certainly wasn't our best game by any stretch, but we kept finding a way to keep ourselves in it."
Marleau has five goals in the last two seasons against the Stars. ... Left winger Ryane Clowe (knee), defenseman Brad Norton (back) and center Marcel Goc (back) were out for San Jose. ... Earlier in the day, the Stars announced that defenseman Philippe Boucher will go on IR and miss at least four weeks because of shoulder surgery. Boucher has been playing through the injury thatTippett described as "normal wear and tear," and Boucher stayed in the lineup until Norstrom was healthy enough to be activated earlier this week. Norstrom has recovered from a facial injury and played for the first time since Nov. 7. ... Right winger Junior Lessard was recalled from Dallas AHL affiliate in Iowa to replace Boucher. Lessard had eight goals and 10 assists in 21 games for the Iowa Stars this season.