MONTREAL — It was supposed to be an uneventful night for goaltender Braden Holtby, who was supposed to stay in his seat in the tunnel to the Washington Capitals’ locker room. He was supposed to take the next few days to get back into his routine and then get back in net on Wednesday.

But after the Montreal Canadiens scored three goals on Pheonix Copley in the first two minutes of the second period, what was supposed to be the plan for Holtby abruptly changed. He fastened his mask and skated over to the Capitals’ net to replace Copley and make his first appearance since suffering an undisclosed “upper-body” injury last week.

And then he did what a top goaltender is supposed to do, stopping 22 shots as Washington clawed its way back from a two-goal deficit to beat Montreal, 5-4 in overtime. Center Lars Eller scored the game-winning goal against his former team.

“We had to change the momentum of the game,” coach Todd Reirden said. “Ideally, I wouldn’t have had to play Braden, but sometimes your plan has to change. I thought he was great when he came in.”

The Capitals closed their road trip with six points out of a possible eight while dealing with injuries to top center Evgeny Kuznetsov and right wing T.J. Oshie, who both took blows to the head against the Winnipeg Jets on Wednesday night and haven’t been on the ice since. Through the first 20 games of the season, Washington is now 10-7-3. The team’s play is still uneven at times, but it is largely trending in the right direction. Against the Canadiens, the Capitals had to contend with an all-world goaltender in Carey Price while they got a significant lift from their own netminder.

After goals from Brett Connolly and Alex Ovechkin, the Capitals had a 2-1 lead to start the second period. But within two minutes of the puck dropping, they were in a two-goal hole. Brendan Gallagher drove the net on the first shift to punch Phillip Danault’s feed past Copley just 20 seconds into the period. Capitals defenseman Madison Bowey was called for interference

32 seconds later, and it took just 16 seconds for Jeff Petry to score on the Montreal power play. Then, at the 1:35 mark, Kenny Agostino scored the Canadiens’ third goal of the period, prompting Reirden to signal for Holtby.

Holtby got hurt in Winnipeg during an informal on-ice session with goaltending coach Scott Murray on Wednesday morning. He returned to practice for the first time Sunday afternoon in Montreal, and while the Capitals cleared him to dress Monday night, the plan had been for him to start Wednesday against Chicago.

“I felt more comfortable as it went on,” Holtby said. “Cops has been playing phenomenal for us, and a couple bounces don’t go our way, we know it’s not on him. It’s on us to pick a teammate up in that situation. I thought our team really turned it around and started playing some good hockey.”

The Capitals started their comeback 13:20 into the period, when defenseman Christian Djoos’s centering pass bounced off a skate in front of the net, and it caromed straight to center Nicklas Backstrom in the high slot. With Kuznetsov and Oshie both out for a second straight game, Backstrom has picked up some of the slack with two goals and an assist in the past two games.

So has Ovechkin. With the Capitals on a power play to start the third period, Ovechkin slapped a shot past Price to tie the game, 4-4, with his third goal in the past two games and second of the night. He now has 15 goals this season.

Then Price’s sliding save on Ovechkin with the nob of his stick in the final second of regulation was so spectacular that Ovechkin applauded on the ice and then gave Price a pat in acknowledgement. That save ensured overtime and at least a standings point for both teams.

“It was a pretty cool moment, a pretty beautiful save,” Ovechkin said. “The fans were cheering for him, and I was kind of the same.”

Said Price: “He’s had my number for a while, so it was nice to get him back once.”

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