ST. LOUIS -- Marian Hossa kept his eye on the bouncing puck, all the way to the winning goal.
"I saw their defenseman had trouble handling it," Hossa said. "It was just a lucky takeaway from him, and I just had to shoot it."
Ilya Kovalchuk scored his NHL-leading 29th goal for the Thrashers, who have won four in a row in a six-day span.
"It would have been easy for us to roll over," coach Don Waddell said. "We could have been very satisfied with the weekend, but you could see the energy."
Hossa swept in alone on goalie Manny Legace after Jay McKee fumbled the puck in the air and then lost control after Eric Perrin flipped it into the St. Louis zone. McKee said he was trying to swat the puck out of the slot to fellow defenseman Barret Jackman.
"That's not a puck you want to control with a guy like Hossa bearing down on you," McKee said. "Just when the puck hit the ice, it was a tough bounce and it's unfortunate in a game that we battled for ends that way."
The Thrashers beat Montreal by the same score in a shootout on Saturday, and their winning streak comes after losing their previous four games. They won in St. Louis for the first time in franchise history.
Kovalchuk has 25 goals and 16 assists in the last 28 games for the Thrashers, who climbed above .500 at 18-17-1. Mark Recchi tied it in the third period with his fourth goal in seven games since being claimed off re-entry waivers on Dec. 8.
Keith Tkachuk had a goal and an assist for the Blues, giving him six points in three games. Tkachuk has a goal in each of the last three games, giving him a career total of 482, after being limited to eight assists in the previous 15 games.
Jackman added his first goal of the season and only the 12th of his career. St. Louis won 4-1 on Saturday in Boston, and coach Andy Murray thought the team looked flat.
"I'm not making excuses. I just didn't think we had energy," Murray said. "But I knew this one would be tough."
The Thrashers had been 0-3 in St. Louis, getting outscored 11-1, since entering the NHL in 1999-2000.
The 39-year-old Recchi, who landed with Atlanta after the Penguins had sent him to Wilkes-Barre/Scranton of the AHL, tied it at 10:42 of the third, scoring off a rebound on a power play. The Thrashers dominated in the third period, outshooting the Blues 9-3.
"Our third period was outstanding," Recchi said. "To come in here and play the way we played it's an indication of how much the guys are really buying in and want to be successful."
Tkachuk scored his ninth goal on a power play at 5:48 of the third, deflecting a pass from the point by Erik Johnson to put the Blues ahead 2-1.
Atlanta had a 9-0 advantage in shots before Andy McDonald got off a quick shot from the slot at 9:35 of a scoreless first period.
Jackman capitalized on a big rebound to put the Blues ahead at 7:08 of the second. Kari Lehtonen couldn't corral the puck on Tkachuk's shot from the left side and Jackman swept in from the point and had a big opening.
Kovalchuk tied it on a power play with a slap shot from the left point. Jamal Mayers was in pain after blocking Kovalchuk's drive earlier in the possession and stuck out his stick on the second shot at 16:22.
"I don't think I've ever seen a shot like that," Recchi said. "Maybe Al Iafrate at one point. I think Manny got a piece of it even and it didn't matter, he shot so hard."
The Thrashers just missed another goal earlier in the period when replays showed Todd White's shot from in front deflected off the crossbar at 3:47.
- Recchi assisted on the Thrashers' first goal and has eight points in seven games. He has 14 goals and 29 assists in 33 career games against the Blues.
- Jackman's season best is four goals in 2005-06.
- It was the only meeting of the season between the two franchises.