Watch: Avalanche's Makar scores controversial goal upheld by offside review

It only took one period for there to be a goal-scoring controversy in the Western Conference Final.

The Edmonton Oilers and Colorado Avalanche exchanged blows throughout a high-powered opening frame, but the home team got the edge when defenseman Cale Makar struck with 14 seconds remaining to make it 3-2.

Edmonton challenged the goal for offside. Colorado forward Valeri Nichushkin appeared to be in the offensive zone when Makar pushed the puck over the blue line.

The league determined that Makar didn't make contact with the puck in the offensive zone until after Nichushkin was legally onside, according to the Denver Post's Mike Chambers.

Here's another look at the play:

The Oilers sent the Avalanche to the power play thanks to the failed challenge, which Nazem Kadri capitalized on.

Colorado pushed its lead all the way to 7-3 before the Oilers were able to mount a comeback and make it a one-goal game. Edmonton just fell short, however, as Gabriel Landeskog iced the 8-6 win with an empty-netter.