Colorado Avalanche head coach Patrick Roy, back, argues with referees as center Mikhail Grigorenko, front left, of Russia, points to his bloody mouth, next to center John Mitchell, lower right, during the third period of the team’s NHL hockey game against the Dallas Stars on Thursday. Dallas won 4-3 in overtime.
Colorado Avalanche head coach Patrick Roy, back, argues with referees as center Mikhail Grigorenko, front left, of Russia, points to his bloody mouth, next to center John Mitchell, lower right, during the third period of the team’s NHL hockey game against the Dallas Stars on Thursday. Dallas won 4-3 in overtime.David Zalubowski/Associated Press

Klingberg beat Calvin Pickard with a slap shot on a breakaway just moments into overtime.

The winner came after Jason Demers scored a power-play goal to tie it with 8:40 remaining in regulation. Before that, Niemi turned aside Nathan MacKinnon’s penalty shot.

Jason Spezza and Ales Hemsky each had a goal for the Stars, who won in Denver for the first time since Feb. 4, 2013.

Nick Holden, Blake Comeau and Carl Soderberg scored for Colorado.