Not one, not two, but three one-goal deficits.

That’s what the Avalanche overcame to force overtime on Saturday against the Vegas Golden Knights before surrendering the game-winning goal with 16 seconds remaining in the extra frame at Rogers Place.

With the loss, Vegas earns the coveted No. 1 seed in the Western Conference, Meaning No. 2 Colorado will open the playoffs against the No. 7 Arizona Coyotes on either Tuesday or Wednesday.

It’s a huge challenge. They’re a very good team,” center Nathan MacKinnon said about the Coyotes, who won one of two games against Colorado in the regular season. “They’re well structure, got some good offense. It’s going to be a tough series. We’ll do our homework tomorrow and Monday and we’ll be well prepared and ready to go for Game 1.”

J.T. Compher scored the Avalanche’s third goal with 1:02 remaining to give the Avs one final chance at victory. The goal, which came with the extra attacker, was the result of a strong play from Compher. The centerman battled a Vegas defender in the crease to put home a rebound after his teammate Nazem Kadri’s shot hit the post.

“That’s how the playoffs are. That’s how you score goals, by getting to the net,” Compher said. “It was a good job by our 6-on-5 unit and we were able to pop one in.”

The Golden Knights scored the go-ahead goal in the third period after being awarded a penalty shot. Forward Jonathan Marchessault was hauled down on the breakaway by Avs defenseman Ryan Graves. While it may have been an unavoidable penalty Graves had to take to stop a golden opportunity, the ensuing result was still a goal past goaltender Philipp Grubauer, who stopped 22-of-26 shots in the losing effort.

Colorado was 1-for-6 on the power play and failed to score on a lengthy 5-on-3 when the game was still scoreless in the first period. Even though they eventually added a goal on the man-advantage, the opportunity that may have been the deciding factor was the one early in the third period. Tied 2-2, the Avs drew a penalty in the opening shift of the third but was unable to do much with that man-advantage. Vegas would take a 3-2 lead 30 seconds after killing the penalty.

“I think we’ve been better than we were tonight,” Avs coach Jared Bednar said of his power play. “We do some good things. Even on the 5 on 3, I felt like we were dangerous a couple of times and missed. I think the power play that we scored on we were tenacious on the puck. We kept some plays alive and we kept them extended on the ice and had them tired. It was a good hardworking power play and came up with a big goal at a key time for us.”

Bednar continued: “There was one early in the third period where we didn’t get anything going. We looked sloppy and out of sync. And that to me is focus. That to me was execution. Lack of focus, lack of intensity, just not being on the same page. We have to be better than we were on that power play. We have to accept that there was a responsibility there to try and make a difference and we didn’t do it on that particular one.”

The Golden Knights eventually broke the scoreless tie in the second period on a power-play of their own. After disputing an icing call, one that was eventually overturned, MacKinnon continued to jaw at the official, Chris Rooney, on his way to the bench. Rooney called MacKinnon for unsportsmanlike conduct to set Vegas up for an opportunity to take the lead.

“I’d rather he didn’t take that penalty for sure,” Bednar said. “I just don’t know how much he did in order to earn that penalty. They got the wrong call on the ice and made the correction and brought it center. I’d like to see us leave it at that as a team. I didn’t hear what was said or what was done.”

All three Avalanche goals came from in the crease or close to it. Vegas goaltender Robin Lehner stopped 32 shots in the victory. But aside from a late goal from Compher, a power-play tally from MacKinnon and Joonas Donskoi’s goal in the second, Lehner was up to the task and held the Avs from taking the lead all game.

“We outshot them by about 15,” MacKinnon said. “We had our chances, Lehner played great. But we didn’t execute to the best of our ability. We feel like we have another gear. Nothing to take away from them but we feel like we could’ve buried more of our chances.”