Updated

Washington, DC (SportsNetwork.com) - Alex Tanguay scored twice to back a 40- save effort from Semyon Varlamov, and the resurgent Colorado Avalanche rolled to a 5-1 victory over the Washington Capitals to match their best start in almost two decades.

Rookie sensation Nathan MacKinnon netted his first career NHL goal while assisting on another in Colorado's fifth consecutive win under new head coach Patrick Roy. The Avalanche last began a campaign 5-0-0 during the lockout- shortened 1995 campaign, their final season in Quebec before the Nordiques moved to Denver.

Matt Duchene and Jamie McGinn also lit the lamp for Colorado, with Gabriel Landeskog, Paul Stastny and Andre Benoit each recording a pair of assists in the rout.

Eric Fehr potted the lone goal for the slumping Capitals, now 1-4-0 on the season following their third consecutive defeat. Michal Neuvirth stopped 23- of-28 shots in a losing cause.

"It starts on our end. We've got to be stronger; we've got make sure pucks get out," said Fehr. "I think we need to want the puck a little bit more. We have to win puck battles, whether it's in our end or their end. We need to play physical, and we need to want the puck."

Varlamov, a former Capital who was facing his ex-team for the first time since being traded to Colorado by Washington in July of 2011, continued an outstanding stretch by Avalanche goalies with his latest performance. Colorado has surrendered only four goals during its season-opening tear, with Varlamov going 4-0-0 with a 0.80 goals against average over that span.

"He's playing outstanding," said Roy. "What I like about Varly is he's under control. He's always square to the shooters, he gets out of the net, he's playing with a lot of confidence and he deserves it. The success that he has he has done it on his own."

Colorado quickly set the tone, with Landeskog collecting the puck in the neutral zone and skating up ice before finding Tanguay open in the left circle. The veteran wing fired a shot through Neuvirth's pads to put the Avalanche in front 6:42 in.

Duchene made it a 2-0 game later in the opening period by racing down the right side and sending the puck over Neuvirth's left shoulder just after a Colorado power play expired.

"I thought we were very focused before the game," said Roy. "We jumped at them right from the start. I think we had a really good start. I think the damage was made after going up 2-0."

The Capitals put together a stronger second period, outshooting the Avalanche by a 19-7 margin for the frame. A sharp Varlamov was able to turn aside every chance, however, and Colorado took advantage of a too many men on ice penalty to extend the margin further.

An on-point behind-the-net centering pass from Stastny found its way to MacKinnon in the right slot, with the 2013 No. 1 overall pick blasting home a one-timer to put the Avalanche up 3-0 with 2:19 to go in the middle session.

Washington began the third period on a power play, but ended up falling behind further when Neuvirth failed to cover up the right side of the net and Tanguay found an opening with a low snap shot in a shorthanded situation at the 1:19 mark.

That set up a wild sequence of three goals within a span of 65 seconds. Fehr crashed the net to tip in a centering feed from Jason Chimera to get Washington on the board, but the Avs answered a mere 21 seconds later. A Capitals turnover led to a 3-on-2 rush that resulted in McGinn beating Neuvirth with a high wrister that increased Colorado's advantage to 5-1.

Game Notes

Washington defenseman Nate Schmidt made his NHL debut in place of John Erskine, out with an upper-body injury ... Avs blueliner Ryan Wilson returned to action after missing the team's first four games with a preseason knee injury ... Stastny's assist on MacKinnon's goal was his 400th career NHL point ... Varlamov and Neuvirth were each selected by the Capitals in the first two rounds of the 2006 draft, with Varlamov the 23rd overall pick and Neuvirth taken 11 spots afterward ... Tanguay's goals were his first with the Avalanche since Game 3 of the 2006 Western Conference Quarterfinals against Dallas. The 33-year-old spent his first six NHL seasons with Colorado from 1999-2006 and was traded back to Avs by Calgary in June.