After the officials initally ruled no goal on Ovechkin's attempt, the Situation Room initiated a video review and determined Rangers goalie Alexandar Georgiev threw his stick.
"I knew 100 percent it was a goal because it was an empty net," Ovechkin said. "He threw his stick, but I was surprised the first reaction from the ref (was no goal). It's nice that they have replay."
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Rule No. 25.4 states, "A goal will be awarded when a goalkeeper attempts to stop a penalty shot by throwing his stick or any other object at the player taking the shot or by dislodging the goal."
Georgiev said: "It's tough to explain, but he faked the shot and I went down earlier, and then as he was moving, I kind of threw my leg and the stick at the same time. It's a tough call. I feel like I had my pad on the ice at the moment he was about to shoot. It's not like the empty net was there. Tough call."
Carl Hagelin and Andre Burakovsky scored for the Capitals (38-21-7), who are two points ahead of the New York Islanders for first place in the Metropolitan Division; the Islanders lost to the Philadelphia Flyers 4-1 on Sunday. T.J. Oshie and Nicklas Backstrom scored in the shootout.
Washington has won four straight games and is 10-3-1 in its past 14.
"As soon as it happened, I thought it was going to be a goal instantly, I'm not sure what the delay was," Holtby said. "That's the rule, [Ovechkin] would have had a wide-open net. They made the right call and it was a big win. It's good that the League was on top of it, that's the way it should be handled."
Ryan Strome and Pavel Buchnevich scored, and Georgiev made 37 saves for the Rangers (27-27-11) who have lost four in a row and are 12 points behind the Montreal Canadiens for the second wild-card into the Stanley Cup Playoffs from the Eastern Conference.
Georgiev made the save on six shots by Ovechkin in the game, including a breakaway at 1:54 of overtime.