"It's always fun to come back and play against a former teammate and have a good time," Byfuglien said. "At the same time we're here to do a job and we can't ease up on him. We wanted to put as many shots on him as we could. He's a pretty quiet guy, a good kid, and he has a bright future."
Cross Checks Blog
Scott Burnside and Pierre LeBrun write about all things happening in the NHL. Cross Checks
Dany Heatley and Ryane Clowe scored within 21 seconds of each other in the first period for the Sharks, who had their home opener spoiled.
Chris Mason stopped 37 of 39 shots to earn his second regular-season victory against the Sharks in 11 meetings. Niemi stopped 24 of 28 shots in losing his first game with the Sharks.
"You don't come in here and win too often," Mason said. "It makes for a great road trip."
Niemi won a Stanley Cup with the Chicago Blackhawks last season and faced four of his former teammates, including Ladd and Byfuglien, who scored three game-winning goals during a sweep of San Jose in the Western Conference finals that put Chicago in the Stanley Cup finals for the first time since 1992.
"He has a great shot," Niemi said. "When he gets the puck he knows how to score. You just have to be ready to make those big saves."
Heatley's first goal of the season was also the 300th of his career. It came after Patrick Marleau's shot bounced free to Heatley at the top of crease.
Mason and the Thrashers defense clamped down on the Sharks afterward, getting a pair of second-period goals from Ladd and Stewart.
Ladd scored the short-handed goal after picking up the rebound of Bryan Little's shot and knocking it off Dan Boyle's skates.
"We had many battles during practice last year so it's kind of fun to put one past a guy you played with," Ladd said. "He doesn't say much but you know he was a little upset that got past him."
Stewart, who scored four goals in his first 108 NHL games, scored his fourth in the past two days with 6:02 left in the second period, allowing the Thrashers to pull even.
"Stewy is playing unbelievable," Little said. "Anything he gets, he's burying. We have to keep riding him."
Byfuglien scored on a power-play to give the Thrashers the lead. Kane added his goal four minutes later.
"We did a few good things," Mitchell said. "But we have to sharpen up our play."
The Sharks played their first game in a week after opening the season with two games in Sweden. Atlanta was coming off a shootout win over Anaheim on Friday night.
"There was a lot of rust that showed later in the game," Sharks' center Joe Thornton said. "We made a couple of giveaways that cost us. When you make a bad play it usually ends up in the back of your net."
Atlanta D Tobias Enstrom played in his franchise-tying 251st consecutive game, matching Slava Kozlov. ... The Sharks are 6-10-2-1 in home openers. ... Thornton signed a three-year extension before the game.