Montreal defenseman Patrick Traverse was penalized for interference with 2:11 to go in the third period, putting Tampa Bay on its fourth power play. Andreychuk cashed in, wristing a high shot from the left faceoff circle that beat goaltender Jose Theodore to the stick side.
It was the 13th goal of the season for Andreychuk, the most prolific power-play scorer in NHL history.
Midway through the third period, Koivu was taken down from behind by Fredrik Modin. Taking the first penalty shot of his career, the Canadiens' captain deked from his backhand but was denied by a sprawling Khabibulin.
Koivu has a goal and an assist for Montreal, which is 1
Ruslan Fedotenko also scored for the Lightning, who have just one win in their last seven games (1-3-2-1).