Eyssimont gave the Bruins a 2-1 lead 39 seconds later at 14:55. He scored on a one-timer from the left hashmarks after Tanner Jeannot cut through the neutral zone to create a 2-on-1.
Geekie extended the lead to 3-1 with five seconds remaining in the second period. He recovered a loose puck behind the net, quickly cut back and stuffed the puck past Wedgewood on the short side.
"That was the biggest goal of the game," Sturm said. "Going into the third period with a two-goal lead was huge for us. There was only a few seconds left … and that was the biggest play of the game today."
Lehkonen scored his second of the game to get Colorado within 3-2 with 20 seconds remaining and Wedgewood pulled for an extra skater.
Prior to the team's practice Friday, the Bruins players held an hour-long meeting about what they needed to do to end the losing streak.
"It feels good to beat one of the top teams in the League," Swayman said. "To get it done at home shows the resiliency we have in this locker room and it's something we can really build on."
Boston had a season-high 34 blocked shots, and was 3-for-3 on the penalty kill.
"It's the best thing ever," Swayman said. "It's a momentum shifter in a game when guys are sacrificing their bodies for the greater good of the team. That's important for us and gives us a ton of momentum moving forward and I'm really thankful to have these guys in front of me."
NOTES: Bruins defenseman Jordan Harris, who is on injured reserve and has missed the past two games with an undisclosed injury, will be out "for a bit" and could have surgery, Sturm said. … Boston defenseman Hampus Lindholm, who was a game-time decision, missed his fourth straight game with an undisclosed injury. … Avalanche defenseman Cale Makar assisted on Lehkonen's first goal and has a point in each of Colorado's first five road games of a season for the second time in his career (also five games in 2024-25). Only two defensemen in Avalanche/Quebec Nordiques history have posted a longer stretch to start a season: Jeff Brown (eight games in 1986-87; John-Michael Liles, six games in 2010-11).