Mikko Rantanen scored a power-play goal at 4:43 of the third period to tie the game 1-1.
Logan Couture scored on the power play 1:17 later to give the Sharks a 2-1 lead. He beat goalie Jonathan Bernier with a wrist shot from the left face-off circle to the far side.
"We tie it, and all of a sudden we're back down 2-1," said Avalanche forward Nathan MacKinnon, who has not scored in nine games. "We played hard. It stings to lose like that."
Joonas Donskoi made it 3-1 at 10:14 with a backhand past Bernier from close range.
Blake Comeau redirected David Warsofsky's shot past goalie Martin Jones at 13:06 to cut San Jose's lead to 3-2, but Colorado had three shots on goal the rest of the game.
Tomas Hertl scored into an empty net with two seconds left to make it 4-2.
The Sharks squandered a 2-0 lead and lost 4-2 to the Dallas Stars on Tuesday. This time, they responded to push from the Avalanche.
"They tied the game and I'm sure everyone's thinking about the other night," Sharks captain Joe Pavelski said. "So, for us to come out and get a power play and execute on it and stick one in the net, that was important. It just kind of proves that this team has a good mindset and good character to come back and forget about things."
Jones made 23 saves, none bigger than when he stopped Gabriel Landeskog's wrist shot from the slot with his blocker with 1:22 remaining.
"That was huge," Braun said. "I asked him if he saw it. He said he saw it the whole way. That's why he's back there, one of the best in the League. It was good to see that one up in the netting."
The Avalanche went 0-2-1 on their three-game California road trip and finished 15-19-7 on the road. They are 25-12-3 at home, and defenseman Mark Barberio said they'll be looking for a home-ice boost Saturday to make the playoffs.
"I think we've done a great job of getting great starts at home," said Barberio, who returned to the lineup after missing 33 games with a lower-body injury. "We come out with energy and feed off our fans. We'll have to take advantage of home ice. This is Game 7 for us. These are the moments we play for: a chance to make the playoffs."
