ELMONT, N.Y. — This Colorado Avalanche team is mortal, after all.

The New York Islanders spoiled Brock Nelson’s return to UBS Arena and ended Colorado’s 17-game point streak with a 6-3 victory Thursday night. Not only did the Islanders keep Nathan MacKinnon off the scoresheet for the second time this season, New York put Colorado its first four-goal hole of the season before the Avs made a game of it.

“It definitely wasn’t our best game,” Avs captain Gabe Landeskog said. “We gave up more shots than normal. It felt like we gave up a decent amount of scoring chances, and it just didn’t feel like we were as tight defensively.”

Colorado had the second longest run to start a season with just one regulation loss in NHL history, but dropped to 19-2-6 on the season. Both regulation losses have been on the road — the Avs are now 8-2-4 away from Ball Arena.

The six goals were the most allowed by the Avs this season, as were the 42 shots on goal.

“We had some strange reads and it cost us scoring chances,” Avs coach Jared Bednar said. “And we got out-battled at our net front. Too many rebounds. … That can’t happen We’ve got to be harder at our net front.

“I give them credit. I thought they played a really good game. I thought we fought and tried to stay in it, but we had some guys that didn’t have great nights.”

The Islanders grabbed a 1-0 lead at 5:56 into the first period, even if the Avs didn’t believe it was a legal goal. There was a scramble in the Colorado crease before the puck shook free to Kyle MacLean along the goal line. He spun and fired it into the net while Blackwood was down on the ice with Islanders forward Marc Gatcomb’s stick lodged into his leg pad.

Colorado challenged for goalie interference, but the league’s official review concluded that incidental contact occurred during a scramble for a loose puck in a rebound situation, so it was still 1-0 for the home side.

The Avs had only trailed by multiple goals in three games this season and not since an overtime loss Oct. 26 at New Jersey. New York grabbed a 2-0 lead with 1:40 remaining in the opening period. Mathew Barzal carried the puck into the Colorado zone and made a cross-ice pass to Islanders captain Anders Lee, who beat Blackwood into the top-right corner with a shot from the right circle.

It got worse during a wild second period.

Bo Horvat made it 3-0 when he solved Blackwood on the third attempt of an Islanders rush. Blackwood stopped Horvat’s first first shot, then rookie phenom Matthew Schaefer on the rebound, but Horvat got inside Josh Manson and didn’t miss when given another chance.

Adam Pelech scored 61 seconds later on a harmless-looking shot from the left circle that handcuffed Blackwood, and at 7:59 of the second period in Game No. 27, the Avalanche finally faced a four-goal deficit.

“I didn’t play my best game, that’s for sure,” said Blackwood, who made 37 saves. “You’re not going to win 82 games, even if you want to. I’ll take that (loss) on me. I could have been better.”

Valeri Nichushkin scored 40 seconds after Pelech when he re-directed Sam Malinski’s right point shot. It was Nichushkin’s sixth goal of the season, and his first since returning from missing eight games with lower-body injury.

Less than two minutes later, Martin Necas swooped towards the net from the left wing, went across the front of the crease and tried to pass it back to his left. The puck hit Travis Mitchell’s skate and trickled across the goal line for Necas’ 14th goal of the season at 10:04 of the middle period.

Suddenly, it was a 4-2 games with nearly 30 minutes to play.

But, the Avs took their fourth penalty of the night late in the second period when Cale Makar went to the box for tripping, and Barzal made it a 5-2 Islanders lead with 1:14 remaining in the period.

Makar pulled the Avalanche back within two goals early in the third period when he set up Artturi Lehkonen for a sharp-angle one-timer at 1:27. One Islanders player had a broken stick, and another lost his just before the goal.

MacKinnon, who leads the NHL with 22 goals and 46 points, has only been held without a point five times in 27 games this season — two of the past three times have been against the Islanders.

“We’ve had bad periods, we’ve had bad stretches that we’ve overcome, but I look at a lot of that game and we’re still digging in,” Bednar said.

“It was closer than you think, but it still wasn’t good enough. We’ve just got to make sure the next one is.”

FOOTNOTES: Bednar said before the game that Scott Wedgewood (back) is day-to-day but could still play during this four-game road trip. Wedgewood was removed from the last game, Tuesday night at Ball Arena, because his back tightened up on him. Trent Miner backed up Blackwood against the Islanders.

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