ATLANTA -- The Washington Capitals are turning the Southeast Division race into a one-team show.
The Atlanta Thrashers should need no more convincing of the Capitals' dominance.
The second-place Thrashers are 16 points behind the Capitals in the division.
"They are a highly skilled team with highly skilled players and those players beat us, no way around it," Atlanta defenseman Ron Hainsey said.
Michal Neuvirth stopped 38 shots in the runaway win.
The Capitals, who scored four goals in the third period, matched their season high for a game. They have scored at least four goals in three straight wins.
The Thrashers ended a nine-game losing streak with a shootout win over the New York Rangers on Thursday.
The team's continued struggles could make it more difficult to re-sign Ilya Kovalchuk, who was stopped on seven shots.
"This team is having trouble scoring goals," Atlanta coach John Anderson said. "Our big guns, they have to start scoring goals. We have some guys on the team that are underachieving in the scoring category."
The Thrashers have allowed four or more goals in 11 of 13 games. They had not given up more than six before being overwhelmed by the Capitals.
Anderson said the Thrashers "felt sorry for ourselves" in the third period.
"You can't stop playing, no matter what," Anderson said.
"I capitalized on my chances," Knuble said.
Maxim Afinogenov scored past a diving Neuvirth 14:14 into the second period for Atlanta's only goal.
Washington leads the NHL with an average of 3.51 goals per game. The Capitals almost matched that in the opening 20 minutes. They scored even-strength, power-play and short-handed goals in the first period for a 3-0 lead despite being outshot 18-7.
"It's hard to say you got off to a good start when you are down 3-0, but the start was there," Hainsey said. "We had our chances. We got none and they got three."
The opening period was a confidence-builder for Neuvirth.
"I had a couple of good saves in the first period," he said. "It was a great 20 minutes for us. It gave me a lot of confidence."
While the young goalie's confidence soared, the Thrashers' frustrations showed.
"In the first period, they were working hard," Washington defenseman Brian Pothier said. "In the second, they seemed a little discouraged. The world caved in on them a little bit."
Knuble scored on a deflection to open the scoring. Semin added a short-handed goal before Backstrom's power-play goal with 19 seconds remaining in the frame.
"The lesson learned tonight is that we need to play better," Hedberg said.
- The Capitals also had eight goals in an 8-2 win at Philadelphia on Dec. 5.
- D Poti's goal was his first of the season. He also had an assist.
- The Capitals have won four straight in Atlanta.
- Thrashers F Nik Antropov (hip) missed his third straight game.
- The game was the first of three straight for the Capitals at Southeast Division opponents. The swing also includes games at Tampa Bay and Florida.
- Neuvirth has played in six of the Capitals' last nine games.