"St. Louis requested a Coach's Challenge to determine whether Sven Andrighetto of Colorado was off-side prior to the Avalanche goal. The video review decision determined the play was off-side but that determination was based on a play prior to the puck clearing the zone.
Per Rule 78. 7 (Note 1) Coach's Challenge: 'Goals will only be reviewed for a potential "Off-Side" infraction if: a) the puck does not come out of the attacking zone again; or (b) all members of the attacking team do not clear the attacking zone again, between the time of the "Off-Side" play and the time the goal is scored.
Although there was an off-side, it occurred prior to the puck clearing the zone which nullifies any goal review related to that off-side. The entry in to the zone immediately prior to the goal was on-side, therefore the goal should have counted."
