Viktor Kozlov had a goal and two assists in the second period and Washington ended Ottawa's team-record eight-game winning streak with a 4-1 victory over the Senators on Thursday night.
The Capitals had lost four in a row and 10 of their past 12 (1-11-1), including a 2-1 overtime loss Tuesday in Atlanta.
"Teams that get on rolls like that, for whatever reason, I don't think they're overconfident but they're ready to be beat and we really stepped it up tonight," said Kolzig, who made 27 saves.
Alexander Ovechkin scored his 10th goal with 3:45 left in the third to restore Washington's three-goal lead after Kozlov, Nicklas Backstrom and Tomas Fleischman scored in the second to put the Capitals up 3-0.
Daniel Alfredsson scored his 11th goal late in the second for Ottawa, which lost for just the second time in 14 games (12-2-0).
"We had our chances in the first and then early in the second, it's a tie game and we got a 5-on-3, and when you lose the game, that's where we kind of look back and say that could have been the difference," Alfredsson said. "We were taking too many penalties and giving them too much momentum for being on the road."
Ray Emery stopped 31 shots in his third start of the season for the Senators.
Washington escaped the Southeast Division cellar and raised its record to 6-9-1 to move one point ahead of Atlanta.
"There's no question we can draw a little bit of confidence from this and there is a little bit of weight taken off our shoulders, but we're still under .500 and we're still a long way from where we want to be," Kolzig said. "But for a young team, we can really use this as a confidence builder."
Capitals coach Glen Hanlon used his timeout midway into the second period after his team killed the first of two penalties on a lengthy 5-on-3.
Hanlon singled out the penalty-killing work done by Boyd Gordon and David Steckel, whose stick broke midway through Ottawa's two-man advantage.
"It was a tough call to call a timeout because their top players were resting, but we just really liked our two penalty killers," Hanlon said. "We felt that it was strength against strength and we felt they'd get the job done, and they did it."
Kozlov opened the scoring with 7:50 left in the second and assisted on 19-year-old Backstrom's first NHL goal, a power-play tally with 5:33 remaining.
"It was nice, and we won the game, too, so that was the most important thing," Backstrom said. "It was just a bonus for me, my first goal, but it was a great feeling."
The big Russian center got his third point when Fleischman stunned the sellout crowd of 19,666 with his third goal with 2:05 left, which put Washington up 3-0.
Alfredsson brought the Senators' fans back to life before the end of the period when he scored his 11th goal with just more than a minute left in the period.
Senators defenseman Anton Volchenkov left the game in the first period because of a bruised right thigh. He did not return.
Kolzig had to come up with his first big stop just 8 seconds in as Chris Kelly tried to beat him with a backhand after receiving a 2-on-1 pass from Patrick Eaves.
"That was something," Kolzig said. "That's happened a couple of times this year and teams have actually scored and it kind of deflates teams a little bit. Guys sitting there going, 'Wow, I wonder what this is going to be like?' But I got my stick on the puck, the D got it back into me and we were able to get regrouped and have a faceoff and go from there, but it definitely got my attention early."
Kelly was also denied by Kolzig on a partial breakaway at 6:28. Alfredsson tested the veteran goalie with a quick shot later in the period, then hit the post on another chance 16 minutes in.
The Capitals broke through to open the scoring on a fine play by Kozlov during a 4-on-4 situation. Ovechkin took advantage of the extra room on the ice to display some of his stickhandling skills as he carried the puck around the Senators' zone before Emery stopped his shot from the slot.
Kozlov got the puck on the right side and cut to the net between the Senators' Randy Robitaille and Wade Redden to put a backhand past Emery.
Backstrom, a fourth overall choice in 2006 who turns 20 on Nov. 23, poked a loose puck past Emery on a goalmouth scramble.
Fleischman made it 3-0 when he fired a shot from the right side over Emery's right shoulder.
Kozlov's goal was his third of the season, his first since Oct. 8, in a 2-1 road win against the New York Islanders. ... Senators C Jason Spezza missed his fifth straight game because of a groin injury. Rookie LW Nick Foligno was Ottawa's only healthy scratch.
Copyright by STATS LLC and The Associated Press
Arena: Canadian Tire Centre Location: Ottawa, Ontario
Referees: Kerry Fraser, Dan O'Halloran Linesmen: David Brisebois, Mark Shewchyk
Attendance: 19,666 (106.3% full)
Team Stat Comparison
Power Play Goals
Power Play Opportunities
Shots on Goal
No scoring this period
Viktor Kozlov (3)
Assists: Alex Ovechkin, Shaone Morrisonn
Nicklas Backstrom (1)
(Power Play) Assists: Viktor Kozlov, Michael Nylander
Tomas Fleischmann (3)
Assist: Viktor Kozlov
Daniel Alfredsson (11)
Assists: Mike Fisher, Dany Heatley
Alex Ovechkin (10)
Assists: Brooks Laich, Michael Nylander