Heatley declared himself significantly better than Tuesday night, when he played at less than full strength due to an unspecified injury in a 2-1 San Jose win.
Heatley sat out a 1-0 overtime loss in Game 3 with the injury.
Meanwhile, Colorado center Kevin Porter returned to the Avalanche lineup for Game 5 on Thursday night.
Porter, who did not have a point in the first two games, missed Games 3 and 4 with an upper body injury.
Porter said he wanted to get back in there and make a difference in the series, which was tied 2-2.
The Associated Press contributed to this report.