"I was surprised Dany was able to pull away," Sharks coach Todd McLellan said. "He was tired and at the back end of a shift. We were actually trying to get him off."
San Jose's Patrick Marleau tied it with a power-play goal with 7:09 left in regulation, and Evgeni Nabokov made 28 saves. Tied for the NHL lead with Chicago with 63 points, the Sharks have won nine of their last 10 games.
"He got rewarded for blocking a shot," Nabokov said about Heatley's winner. "He was tired too, but he did a good job. I got excited and thought, 'There he goes, he's got the breakaway.' Those guys play us hard every single game but we stayed with it."
Andy McDonald scored in his fourth straight game for the Blues, who lost their sixth straight and second since interim coach Davis Payne took over Saturday following Andy Murray's firing. Mason made a season-high 42 saves for St. Louis.
"We played with a lot more structure and came out strong," McDonald said. "They scored on a power play on a penalty on myself and that's a hard pill to swallow."
Heatley blocked McDonald's shot to start the winning sequence. He got a step on a pair of Blues' defenders and beat Mason.
"I was going to wait and see after I got a little step on the guys," Heatley said. "I played with Mason last year in the world championships so he knows my game. It was more of a split-second decision on the shot."
The Blues were missing two of their top offensive stars in Keith Tkachuk and Paul Kariya, two noted Sharks' killers. Tkachuk remained at home following his mishap with broken teeth in the Blues' 6-3 loss to Chicago on Saturday.
Kariya, who missed his fourth game because of concussion-like symptoms, skated during the pregame but wasn't well enough to play.
Tkachuk has 33 career goals against the Sharks, his second-most (34 vs. the Blackhawks) against any team. Kariya has 60 points against San Jose, his fourth-highest total against any team.
McDonald, who scored his 14th goal, helped his own cause. He was pushed into Nabokov during the power play and they both went to the ice. McDonald got up faster and took advantage to slip the puck into the net against a defenseman with 13:15 remaining in the second period.
"I think we made some progress," Payne said. "I though all four lines, all six defensemen and Chris Mason played a heck of a game."
Blues defenseman Barret Jackman saved a goal by pouncing on the puck and using his glove to bring it back from near the line.
Marleau's tying goal was set up when Ryan Clowe won the puck along the boards and dished out to Dan Boyle, who faked a shot before guiding it to Marleau, who fired the puck into the upper left corner for his 28th goal of the season.
"I was just trying to find a lane to the net," Marleau said. "Torrey (Mitchell) did all the work up front to screen the goalie and get his stick up."
Heatley then won it with his 25th of the season.
"He started pulling away with his breakaway speed and the rest of us were all on the board waiting for him to put it in," Marleau said.
Blues' C Alexander Steen has points in five of his last six games. ... Blues RW David Backes has four assists in his last three games. ... Boyle was hit in the face by a puck in the second period and was able to walk off the ice on his own. He returned to the bench for the third period. ... Marleau has scored goals in three straight games. ... Mason is 1-8-0-1 against the Sharks. ... Mitchell played in his 100th game.
Copyright by STATS LLC and The Associated Press
Arena: SAP Center Location: San Jose, California
Referees: Paul Devorski, Dan O'Rourke Linesmen: Steve Barton, Vaughan Rody
Attendance: 17,562 (100.4% full)
Team Stat Comparison
Power Play Goals
Power Play Opportunities
Shots on Goal
No scoring this period
Andy McDonald (14)
(Power Play) Assists: David Backes, Alexander Steen
Patrick Marleau (28)
(Power Play) Assists: Dan Boyle, Ryane Clowe