Doug Weight assisted on all four St. Louis goals, giving him nine assists in his last five games. Dan Hinote and Bryce Salvador also scored for the Blues. Ken Klee scored for the Avalanche, who outshot the Blues 45-29. Colorado has recorded 30 or more shots in 10 of its 13 games this season.
Legace, who did not start the previous two games, improved to 9-1 against Colorado in his career. After coming over from Detroit as a free agent, he is 3-3-1 this season with St. Louis.
The victory snapped a three-game losing streak for the Blues, who were winless in four games against Colorado last season. The Avalanche dropped to 5-1-2 in their last eight against St. Louis.
Hinote, who spent his first six NHL seasons with the Avalanche before signing with St. Louis in July, scored at 11:17 in the first period to give the Blues a 1-0 lead. Hinote came out of the penalty box and took a pass from Weight past the red line. Hinote skated in on the left side, went around Colorado defenceman Patrice Brisebois and beat goalie Peter Buidaj for his second of the season.
St. Louis took a 2-0 lead on a goal by Guerin at 1:42 of the second. From behind the net, Weight passed to Guerin, who one-timed the puck from the slot. Signed as a free agent in July, Guerin has at least one point in eight of the Blues' 12 games this season.
The Blues went ahead 3-0 when Salvador scored from the right circle at 16:57.
Colorado quickly answered on Klee's first goal of the season at 17:27, cutting the lead to 3-1.
Guerin scored his second goal with 2:35 remaining. Standing near the left post, he took a pass from Weight and knocked it in from just outside the crease.
Notes: This was the first of four meetings for the teams this season. ... Colorado was the least penalized team in the NHL during October. ... Claimed off waivers Tuesday from Phoenix, centre Joel Perrault has yet to play for the Blues, who lost 4-1 Wednesday at Dallas. ... Colorado defenceman Karlis Skrastins extended his consecutive games played streak to 446, the longest active streak in the NHL and second-longest by a defenceman in NHL history.