• In their last 12 games against the Blues, the Capitals have two wins (nine regulation losses, one tie).
• Since Oct. 28, Washington is 15-1-0 in games in which it scores the first goal and 1-6-2 when its opponent scores first.
• In its last 10 losses, St. Louis has scored just 21 goals.
-- ESPN research
Kozlov had two goals and an assist and Washington extended its winning streak to five games with a 4-2 victory over struggling St. Louis.
"He's the unsung Russian," Capitals coach Bruce Boudreau said of Kozlov. "He just goes out and does his business."
Tomas Fleischmann and Ovechkin also scored for the Capitals, who have won seven of eight and improved to 13-1-1 at home. Simeon Varlamov, summoned from AHL Hershey because Jose Theodore is sidelined with a hip flexor injury, made 29 saves. He has won both of his NHL starts.
Kozlov deftly deflected the credit to Varlamov, who displayed the poise of a veteran and spoke instead of team goals.
"As long as we kept the winning streak going and got the two points, everyone's happy," Kozlov said. "We can't relax. We have to stay focused and play the same way."
David Backes scored for the third consecutive game and Brad Winchester also had a goal for the Blues, who have dropped five straight. They were the only ones who figured out Varlamov, whose father Alex watched his son play in the NHL in person for the first time.
"I try not to think about it, but it's great his dream was realized, his dream to see me play in the NHL. It was my dream as well," Varlamov said through an interpreter. "He's probably the happiest man in the world right now."
Three Capitals goals in a span of 3:07 beginning late in the second period turned a 1-1 tie into a one-sided affair. Washington notched its 20th victory in its 33rd game. Last season, it took the Capitals 46 games and until Jan. 17 to reach that mark.
Blues coach Andy Murray lamented the opportunities his club gift-wrapped for Washington, a team with a penchant for pouncing on errors.
"We know they're a good and dangerous team. I didn't like some of the things they did to allow them to get scoring chances," he said.
While Murray pondered another loss, Boudreau said Washington has room for improvement.
"It's still before Christmas and I think we can play a lot better," Boudreau said. "We can shut them down better, and our power play wasn't really good. I don't know if we've hit our stride yet."
Kozlov broke a scoreless duel 16:14 into the first period with his sixth goal. He took a pass from Nicklas Backstrom in the left corner, skated out and snapped a shot over the right shoulder of goalie Ben Bishop.
A tip-in by Backes tied it midway through the second period. Backes skated to the left post, where he deflected Jay McClement's fluttering shot from the left wing.
Kozlov and Fleischmann scored 40 seconds apart late in the second period, giving Washington a 3-1 lead.
Trailing the play, Kozlov backhanded Boyd Gordon's rebound past Bishop at 17:06. Fleischmann, left unguarded between the circles, snapped in his 11th goal.
Just 13 seconds into the third period, Ovechkin took Kozlov's feed and converted on a power play from the top of the left circle.
Winchester's power-play goal made it 4-2 with 8:26 left.
Kozlov's previous two-goal game was on Jan. 21, 2008, at Pittsburgh. ... Washington played without defenseman Tyler Sloan (leg) and center Sergei Fedorov (ankle). ... St. Louis defenseman Tyson Strachan made his NHL debut. ... The Capitals' winning streak matches a season high set from Nov. 6-14. ... Semin left with 11 minutes remaining in the game after being crosschecked from behind by Backes near the boards. Boudreau said Semin would be re-evaluated Friday.