Gabriel Landeskog, Mikko Rantanen and Nathan MacKinnon each had a goal and an assist for the Avalanche, the No. 1 seed in the Honda West Division. Colorado will play the winner of the first-round series between the Vegas Golden Knights and Minnesota Wild; Vegas has a 3-1 lead in the best-of-7 series.
Philipp Grubauer made 18 saves for the Avalanche, who outscored St. Louis 20-7 in the four games.
"I think it's huge to get a couple days, but most important how we played every game, 60 minutes, every shift," Grubauer said. "Every, every small detail matters in the playoffs. I think we found a way to do that in every game and that's going to be the key moving forward too."
Vladimir Tarasenko scored twice, and Jordan Binnington made 29 saves for the Blues, the No. 4 seed, who were eliminated in the first round for the second straight season after winning the Stanley Cup in 2019.
"To tell you honestly, I'm not ready for these questions right now," Tarasenko said. "To answer all of those is there's no excuses. I can [say] whatever I want to say, and say like we don't fight enough, but it is what it is. This is embarrassing. [It's] always hard to lose in the playoffs, especially like this. There [are] no words, that much you can see."