THE STORY
On October 19, 2017, the Colorado Avalanche scored a late third-period goal against the St. Louis Blues to tie the game. The goal by Mikko Rantanen was disallowed after the Blues challenged for offside involving Sven Andrighetto. The NHL later admitted the challenge was incorrectly allowed since the play was not reviewable, and the goal should have counted. This was the first such error since coach's challenges were introduced in 2015-16.
WHY IT MATTERS
This incident highlighted the limitations and potential for error within the coach's challenge system, leading to discussions about the need for clearer guidelines and more precise officiating in the NHL.