"We needed a win," Vegas coach Peter DeBoer said. "We've been putting in some pretty good work. We had an opportunity to win a couple of the last few games in the third period and didn't do it. We needed one. Really short bench in the third and a lot of tired guys, but guys dug deep and really proud of the effort."
Chandler Stephenson had a goal and an assist, and Robin Lehner made 26 saves for Vegas (2-4-0).
"Big one for Robin," DeBoer said. "Robin's been really solid, but he needed to get rewarded with a win and he needed some goal support, and we haven't given him that. He got both of those tonight."
Cale Makar scored, and Darcy Kuemper made 26 saves for Colorado (2-4-0), which has lost four of its past five games.
"We're sort of stumbling and bumbling along right now, so there's a level of concern," Avalanche coach Jared Bednar said. "It's not like, 'Well we just didn't play good tonight and (we're) moving on to the next (game).
"To me, this is a big game because part of what we talked about today was that if we win tonight and we're able to get to .500, now we can start (moving) above .500 if we do our job. If you lose, you drop two games back, and now we'll see how long it takes us to get back (to .500). It could be seven days, it could be 10 days, it could be a month."
Stephenson gave the Golden Knights a 1-0 lead at 2:00 of the first period, scoring with a backhand after Brayden McNabb's point shot was blocked in front.
"It's huge, you always want to start that way," McNabb said. "I thought we started great. It was great to get that goal, but we played very well with our systems and details. It's something to move on from and use it to our advantage going forward."