At 7:24 of the first period in the Flames/Senators game, Ottawa requested a Coach's Challenge to review whether Calgary's Matthew Tkachuk interfered with goaltender Craig Anderson prior to his goal.
After reviewing all available replays and consulting with the Referee, the Situation Room determined that Tkachuk impaired Anderson from freezing the puck in the crease and pushed his glove with the puck into the net. The decision was made in accordance with According to Rule 78.7, "The standard for overturning the call in the event of a "GOAL" call on the ice is that the NHL Situation Room (which shall include a former referee in the Officiating Department in the decision-making process), after reviewing any and all available replays and consulting with the Referee who made the original call, determines that the goal should have been disallowed due to "Interference on the Goalkeeper," as described in Rules 69.1, 69.3 and 69.4."
Therefore, the original call is overturned - no goal Calgary Flames.
Since the Coach's Challenge resulted in the original call being overturned, the Ottawa Senators retain their time-out.