KANATA, Ont. — The Colorado Avalanche authored a comprehensive performance three days ago in Toronto, but that version of the league-leading club did not travel to the other side of Ontario.

Ottawa stifled Colorado’s high-powered offense in ways no other team has this season en route to a 5-2 victory Wednesday night at Canadian Tire Centre. The Avs finished this game with just 18 shots on goal, easily their lowest output of the season. Mackenzie Blackwood made 18 saves, but Colorado lost for the seventh time in 11 games since a historic 31-2-7 start to this campaign.

“Flat,” Avs coach Jared Bednar said. “Flat — almost the whole team. I don’t want to group everyone in that, because it’s not accurate, but the bulk of our team … flat.”

Claude Giroux gave the Senators a 3-1 lead early in the third period. Senators defenseman Nick Jensen sent the puck up the ice and Giroux was able to beat Parker Kelly to it and create a quick 2-on-1. The 38-year-old kept it himself and snapped a shot past Blackwood just 2:06 into the third.

Valeri Nichushkin halved the Ottawa lead just 84 seconds later. Nichushkin started the possession by carrying the puck into the zone and shot one over the net. Jack Drury stepped in front of a Giroux pass near the blue line and fed Nichushkin all alone in front. He made a quick deke and flipped a backhanded shot past Ottawa goalie James Reimer at 3:30.

It was Nichushkin’s 12th goal of the season. He had gone 10 games without one since a hat trick Dec. 31 against St. Louis. Colorado couldn’t find an equalizer though, and Ottawa added a pair of empty-net goals to end any doubt.

“Not good enough,” Kelly said. “Thought our third period was good. I made a mistake, they’re up 3-1 and we just couldn’t get anything after that. It kind of sucks.”

Nick Cousins put the Senators in front at 3:21 of the opening period. He got behind everyone on the Avalanche and Artem Zub sent a long outlet pass to him at the Colorado blue line near the Ottawa bench. Cousins went straight to the net, beating Josh Manson there before he backhanded a shot past Blackwood on the short side.

Kelly, the ex-Senators forward, scored to tie the game at 14:05. Keaton Middleton found Brock Nelson with an outlet pass, which he directed into the offensive zone. The Avs got a bit of a break when the puck bounced past Jensen and right to Kelly, who beat Reimer for his 11th goal of the season.

It’s Kelly’s first point in four games against his former team after joining the Avs ahead of last season. He now has 20 points this season, which is also a career high along with his goal total.

The Avs gave that one back 17 seconds later. Tyler Kleven sent the puck from just above his own goal line the length of the ice. Ridly Greig got behind Keaton Middleton to nullify a potential icing and when Blackwood hesitated to go play the puck, Greig was able to corral it when it caromed off the end boards and made it a 2-1 advantage.

“Didn’t really feel like we had our legs in the first couple periods,” Avs defenseman Cale Makar said. “It seemed like we were lackadaisical at times. We were still finding chances, but got to hit the net on some of them.”

The less said about the opening period in the suburbs outside the Canadian capital, the better. Colorado didn’t have a shot attempt until Sam Malinski’s long-range attempt at 7:05. The Avs finished the period with just five total — four on net. Nathan MacKinnon’s backhanded attempt with 3:22 remaining in the period was the team’s only one from inside 45 feet.

The final tally was a 17-5 advantage in shot attempts for Ottawa, and 9-4 in shots on goal. Eight of of those shot attempts for the Senators during four minutes of power play time. The Avs generated 0.1 expected goals in the period, which is quite possibly the lowest in any period of the MacKinnon-Cale Makar era.

But Blackwood was also sharp in net when needed, and the Avs were pretty stingy themselves away from the puck.

Colorado’s offense wasn’t much better in the second period. The Avs had just 17 shot attempts after 40 minutes, and eight shots on goal. They finished with 49 shot attempts after a flurry in the third, which was still tied for their fewest in a game this season.

This team began the day tops in the NHL in shot attempts per 60 minutes (70.04) and shots on goal per game (34.9).

Ottawa signed Reimer during Colorado’s 8-2 win against the Senators at Ball Arena three weeks ago. The 37-year-old netminder played one game for the club’s AHL affiliate and this was just his fifth game for Ottawa.

“They did a nice job getting above pucks coming out of the offensive zone, neutral zone,” Bednar said. “Everyone’s kind of doing that now. It’s that point in the season where it’s tough to move through there, but we’re not moving. We didn’t move tonight. When you’re standing still, you can watch our execution … we couldn’t put a pass or two together because we’re not moving.”

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