The Avalanche improved to 5-0 in shootouts this season and are 16-1 since December 2009. Landeskog provided the latest winner when he beat Antti Niemi in the fifth round before Varlamov stopped Brad Winchester to end it.
"I had my plan to come down the right side and kind of go low block," Landeskog said. "Luckily it was open and got the shot off. It was a great feeling when I saw it go in."
It was the rookie's first chance in a shootout.
"It was clutch," Duchene said. "It's his first-ever shootout attempt and he goes in and buries it."
Hejduk scored on the first try of the shootout and Joe Pavelski tied it in the third round.
"We left on the road four days ago, played three games and only gave up seven goals," Sharks coach Todd McLellan said. "Those are pretty good defensive numbers. You should come home with more than two points."
The Avalanche snapped a three-game losing streak and won their fourth straight at home.
"We're trying to recapture some momentum here at home and getting the extra point was critical," coach Joe Sacco said. "Had we not gotten the extra point, I think it would have been a little different mood in the locker room."
San Jose trailed 3-2 late and pressed for the equalizer, getting it with 22 seconds left. With Niemi off for an extra skater, Marleau chipped in a pass from Logan Couture to send the game to overtime.
"I don't think we should have been in that spot to begin with, but it was good to come back with that last-minute goal," Marleau said.
Duchene made it 3-2 with his 11th goal of the season with 8:09 left.
"Hedgie was able to find me in the seam and Landy was doing a great job screening," Duchene said. "I had some room up top and I was able to hit it."
Winnik made it 2-all with his fourth goal of the season and first since Nov. 4. He grabbed Erik Johnson's rebound in front of Niemi, skated around the back of the net and stuffed the puck into the open goal with 13:29 left in regulation.
San Jose tied it early in the second on a power play. With T.J. Galiardi off for high sticking, Boyle sent a shot toward the Colorado net and McGinn tipped it past Varlamov at the 3:16 mark.
It was McGinn's seventh goal of the season.
Boyle gave the Sharks the lead with his second goal of the season. He pinched in, picked up Pavelski's rebound between the circles and beat Varlamov with a wrist shot with 6:21 left in the second period. But the Sharks couldn't hold the lead.
"Second game in a row we had the lead in the third and we gave it away," Boyle said. "It's something that's going to stick out."
Elliott broke a scoreless tie with a great individual effort late in the first period. The rookie picked up the puck in the Colorado end, skated through the Sharks defense and beat Niemi with a shot from the right circle with 16.6 seconds left. It was Elliott's third goal of the season.
The teams generated few quality chances before Elliott's goal. Both clubs had 11 shots in the period.
Colorado C Paul Stastny was back in the lineup after missing three games with a torso injury. ... The Sharks' power-play goal was their first in five games and second in the last nine. ... San Jose is 3-1 in shootouts this season.
Copyright by STATS LLC and The Associated Press
DENVER - DECEMBER 13: Kyle Quincey #27 of the Colorado Avalanche takes to the ice prior to the game against the...