Chris Stewart had a goal and an assist, Chris Durno also scored, Paul Stastny had three assists, and Craig Anderson made 33 saves for Colorado.
In overtime, the Avalanche won the faceoff and Cumiskey skated into the Thrashers' zone. He split two defenders and beat Johan Hedberg for his seventh goal of the season.
Nik Antropov, Niclas Bergfors and Bryan Little each had a goal and an assist for the Thrashers, and Hedberg made 31 saves. Atlanta has lost three straight on the road.
The Thrashers took a 3-1 lead on Antropov's goal with 15:41 left, but Colorado battled back to force overtime. Stewart knocked in his own rebound with 11:26 left, and Durno beat Hedberg with 5:29 remaining in regulation.
Little gave Atlanta a 2-1 lead when his shot from the left circle got past Anderson with 14:28 left in the second period.
The Thrashers thought they had a 3-1 lead when a ruling on the ice gave them a goal with 2:08 left in the second, but a video review showed the puck didn't completely cross the goal line and it was overturned.
Moments after killing a Colorado power play, the Thrashers opened the scoring in the first. Antropov won a faceoff in his own zone and got the puck to Bergfors, who skated into the Avalanche zone and used a screen by Little to beat Anderson.
Colorado struck back 46 seconds later when Clark beat Hedberg.
-- NOTES: Adam Foote played in his 900th game with the Colorado/Quebec organization, the most by a defenseman in franchise history. ... Avalanche C Ryan O'Reilly returned to the lineup after missing a game because of a foot injury.
http://accesswdun.com/article/2010/2/226946