The New York Yankees are currently riding a five-game winning streak and have pulled to within 2.5 games in the American League wild-card race. Teams may credit success to many different things, but the Yankees attribute their hot streak to something pretty unusual.

At the beginning of the day on Aug. 21, New York was sitting at 63-61. That’s when reliever Shawn Kelley decided to wear a horse-head mask during the team’s pregame stretch.

The team has not lost since, so naturally the players believe the mask is a good-luck charm.

Now that the team is winning, the reasoning behind the mask doesn’t really matter. Kelley did explain why he bought the mask, which the players call Seabiscuit, per Yahoo Sports’ Jeff Passan.

“When I see those things, randomly in a crowd, it makes me laugh,” Kelley said. “So I figured I’ll do that, and it’ll make everyone laugh in the clubhouse. And then we went on a winning streak.”

Something like this does a great job to loosen up the clubhouse during a pennant race.

As silly as it may seem, the players are buying into the mask.

“Kelley is undefeated with the horse. I’m never going to go against that,” Yankees outfielder Jacoby Ellsbury said. He added, “At first, I was wondering who it was. And then I wondered why he had it on. And then we got on a little roll, and I figured it doesn’t matter what the reason is. We’re winning with it.”

The Yankees are averaging 5.4 runs per game and allowing just 2.2 runs per game since Seabiscuit made its debut at Yankee Stadium.

A 162-game season is a grind, and once August hits, the pressure for playoff contenders kicks up a notch. That’s why it’s good to have someone in the clubhouse who is willing to do something silly to help keep the team loose.

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