Colorado led 2-0 early in the second period when O'Reilly was taken off the ice on a stretcher after losing his balance and slamming into the boards. A team official said O'Reilly had movement in his arms and legs and was taken to Regions Hospital as a precaution.
"He was moving and it sounds like he's OK," Anderson said. "You've got to find a way to pick him up. It was our job and our duty to win the game for him."
Andrew Brunette scored for Minnesota.
Colorado extended its lead to 3-0 in the second when Fleischmann flicked a shot toward the net from the blue line and the puck bounced between rookie goalie Anton Khudobin's legs. Khudobin was playing because Niklas Backstrom and Jose Theodore, Minnesota's top two goalies, are out with lower-body injuries.
"One goal, but sometimes the goalie has to shut the door. That's the way it works sometimes," Khudobin said.
Once formidable at home, the Wild were booed by the hometown fans after the second period. They are 3-6-1 in their last 10 home games.
The Wild's lone goal came early in the third when Mikko Koivu's spin-o-rama pass from behind the net set up Brunette for an easy goal.
"It's not because of lack of effort or caring," Wild coach Todd Richards said. "We created chances and that's what you want to do. We need either that extra effort to finish or we need a fortuitous bounce."
Cody McLeod also returned after missing the last eight games with a groin injury.
Avalanche coach Joe Sacco was glad to have both guys back, but talked after the game about his team's focus after O'Reilly went down.
"What I tried to right after that happened and he went off was just tell the guys that he was going to be fine and make sure that we stayed strong within the game," Sacco said. "Sometimes you tend to drift a little bit when you see a teammate go off like that. It's just human nature."
Wild forward Cal Clutterbuck talked some trash after Minnesota beat the Avalanche on Dec. 23, leaving some to speculate that Colorado players could seek revenge on Friday.
There was a minor scuffle 27 seconds into the game, but no further incidents.
Porter and Hejduck scored in the first period. Wilson added an empty-netter late in the third.
After a brief goal-scoring outburst last week, The Wild's scoring woes have returned. Minnesota has scored just one goal in three straight games.
"We're just not scoring goals," Wild defenseman John Madden said. "We hit three goalposts in the first period I think and pucks are going just wide, so we're not getting any bounces. You can't score one goal a game and expect to win."
Wild coach Todd Richards didn't know if Theodore would be ready for Sunday's game against Vancouver. Backstrom skated in the morning and could be ready by Tuesday. ... The Wild recalled D Jared Spurgeon before the game and assigned F Patrick O'Sullivan to Houston of the AHL. The Wild also recalled Matt Hackett to back up Khudobin. ... The Avalanche placed winger Greg Mauldin on waivers to make room for Stewart. ... Hejduk's goal was Colorado's first in its last 29 power plays. ... Wild D Marco Scandella left the game in the third and didn't return after getting hit in the head with the puck.