Colorado's top winger found the back of the net three times but it wasn't enough for a win.
Mikko Rantanen scored his eighth career hat trick and Nathan MacKinnon surpassed 900 career points in the Colorado Avalanche's 8-4 loss to the Vegas Golden Knights on opening night.
The 27-year-old Finn is fourth in franchise history for hat tricks behind Peter Stastny, (16), Joe Sakic (15) and Michel Goulet (13). His trio of goals in the first game of the season was the sixth occurrence in Avalanche/Nordiques history.
At the end of the day, the milestones do not matter if the end result is a loss. Rantanen said the team will regroup and learn from the mistakes it made to be ready for the home opener against the Columbus Blue Jackets on Saturday.
"I feel like every time we got close to them they right away almost scored right back. Couple times one-goal game, then next shift it's two-goal game again," Rantanen told media after the game. "Defensively got to look at it, and everybody's got to be better. For sure, there's things to clean up."
Alexandar Georgiev allowed five goals on 16 shots through two periods, and was replaced by Justus Annunen who gave up two on four shots. The loss does not rest squarely on goaltending as there were notable mistakes throughout the lineup.
"It's not good enough, but our game wasn't good enough. you can't spend three weeks talking about specific things that you know you have to improve on and then go give up those chances ... ," head coach Jared Bednar said in his postgame conference. "We'll review it, go over it, learn from it, move on."
The frustration for the Avalanche came from the momentum shifts throughout the game. Colorado scored first but then Vegas answered with three goals to end the first period 3-1.
Rantanen scored his second to pull within one and then Zach Whitecloud made it another two-goal gap at 14:11 in the second. Casey Mittelstadt scored with less than two and a half minutes left to pull back within one, but then Victor Olofsson got one past Georgiev in the last 30 seconds to end the middle frame 5-3.
Rantanen scored his third to bring the Avs back into range but defensive mistakes allowed the Golden Knights to secure the win with two more and an empty-netter.
The loss on opening night was the team's second time in the last five years and third in the last 10.