KANSAS CITY, Mo. – At the bottom of Shawn Kelley's locker sat 1.1 pounds of horror. It had giant nostrils and a full set of teeth and frightened brown eyes and a lovely mane. It is the New York Yankees' new good-luck charm.

Last week, Kelley found himself ensnared in the spider web of Amazon.com when he came upon a horse head mask offered by a company called Accoutrements, which also peddles a pickle that yodels, bacon-flavored lip balm and an inflatable unicorn horn for cats. The horse head garnered more than 3,000 ratings and a 4½-star consensus. Kelley, a Yankees relief pitcher, needed no further convincing.

"When I see those things, randomly in a crowd, it makes me laugh," he 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."

Since he debuted the horse head during the Yankees' pregame stretch Thursday, they are 5-0, including a 8-1 shellacking of American League Central-leading Kansas City on Monday night. It is the Yankees' first five-game winning streak in more than four months, and however much credit one wants to give the reinvigorated starting rotation or reimagined lineup, the truth is much simpler.

"Kelley's undefeated with the horse," Yankees center fielder Jacoby Ellsbury said. "I'm never going to go against that."

View photos The Yankees are 5-0 since Kelly introduced his horse head. (AP) More

The mask, according to its product page, is made of latex and an "awesome conversation piece." It continues: "We've discovered yet another universal truth – a person wearing a Horse Head Mask looks downright disturbing."

Several Yankees affirmed this truth.

"At first, I was wondering who it was," Ellsbury said. "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."

Since the Equine Era debuted, the Yankees have gained two games in the wild-card standings and 3½ in the AL East. Their postseason hopes, at this point, remain something of a long shot, even with a 68-61 record. Baltimore owns a six-game lead and the Yankees remain 2½ games back of Seattle and two behind Detroit in the race for the second wild-card slot. The Yankees have chased nearly every good stretch this season with a losing streak that negated the gains. They need Michael Pineda – who dominated the Royals on Monday with a fastball that reached 97 mph – to stay healthy, which he hasn't done since 2011. They especially need Masahiro Tanaka, who's trying to rehabilitate a partially torn elbow ligament, to return as a No. 1-level starter.

Should everything go right, the horse head could find itself in Monument Park one day, or at least next to Jason Giambi's rally thong in the annals of the storied franchise. While it's unclear whether a horse-headed fan in Kansas City earlier this year inspired him, Kelley tries to make the performance all his own. He ran around the clubhouse wearing the head after Monday's win and high-fived teammates. He'll bring it on the field before games, looking like a pinstriped Hayagriva.

View photos Kelley (without the mask). (USA Today) More

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