Was it the avocado ice cream? The electrolytes? The gallons of water he consumes daily?

Nope. It was the tape, a big hunk of black tape, that helped Tom Brady play in the AFC championship game despite a cut on his passing hand that required 12 stitches. It might have looked like electrical tape, but this was something called KT Tape, a kinesiology tape designed to relieve pain and support muscles, tendons and ligaments, rather than his line of dietary products that came through in the clutch.

How it came to rest on the golden hand of the NFL’s best quarterback involves a bit of luck as well as Brady’s friendship and relationship with his famous orthopedic surgeon.

On Thursday, Jacki Cassady, KT Tape’s marketing brand manager, was working a booth at a conference for the Professional Baseball Athletic Trainer Society in Glendale, Ariz., when the doctor who happens to be the chairman of the conference approached and said he knew a New England Patriots player who needed tape to cover his thumb while allowing him to flex his hand. The man cut a strip of tape in half and tested it on his thumb, with an assistant taking photos.

The New England Patriots won the A.F.C. championship game on Jan. 21, as quarterback Tom Brady reportedly feuds with the team's leadership. (Reuters)

“He said he was looking into it to cover an abrasion and wanted to wrap it around his finger, which isn’t a typical application — it usually would be wrapped then around the wrist,” Cassady said. “I asked for a card, but he wouldn’t share it with me, so I referred him to Ed Terris, who is our lead sales guy.”

The mystery didn’t end there. As he left the booth, the man cryptically said, “You may have just saved the game for us.”

By Wednesday afternoon, the man’s identity was a mystery no longer. It was none other than Neal ElAttrache, an orthopedic surgeon and sports medicine specialist who works with the Kerlan-Jobe Orthopaedic Clinic in Los Angeles and has operated on the biggest stars in sports. Not coincidentally, he repaired Brady’s left knee in 2008 and is affiliated with the Los Angeles Rams and Dodgers.

“I was there,” Teri Chavarria, the doctor’s executive assistant, said. “Dr. ElAttrache really likes their products, and he was trying a few things on his hand [at the conference]. Ed had come to our meetings in the past, and we have a relationship with him.”

Getting the tape to New England and onto the cut that Brady sustained in a fluke collision with a teammate Wednesday was another matter. Luckily, Terris, KT Tape’s vice president of sales, was in Philadelphia when he received a text request.

“We get requests like this all the time,” Terris said, and he sent a package containing black Pro Extreme tape and blister patches, which can be applied between the tape and the wound, to 1 Patriot Place in Foxborough, Mass.

By Saturday, the package had arrived. By Sunday, it was visible to everyone on Brady’s hand as he completed 26 of 38 passes for 290 yards (including 138 in the Patriots’ fourth-quarter rally) and two touchdowns in a victory that will take him to the Super Bowl for the eighth time in his career. It isn’t clear at the moment whether KT Tape’s big moment will continue in Super Bowl LII on Feb. 4, because Brady said Monday that he expects the stitches will be removed this week. Neither the team nor Brady has spoken about the tape and how much it contributed to his game, but he did admit Monday that the injury was serious and “didn’t look good there for a little bit. . . . The timing and where exactly it was wasn’t the best thing in the world for a quarterback, but it is what it is.”

Kinesiology tape has been around since the 1970s but came into prominence during the 2008 Summer Olympics when U.S. beach volleyball player Kerri Walsh Jennings and other Olympians used it. It formerly had to be applied by medical professionals, but now KT Tape has gone mainstream, with Taylor West, the company’s marketing vice president, telling sporttechie.com that it controls 80 percent of the retail market share.

Just what makes this tape so special? The company’s website says it reduces lymphatic fluid that builds up and causes inflammation, pressure, pain and swelling after injury or overuse. “It is believed that when applied correctly, KT Tape lifts the skin, decompressing the layers of fascia, allowing for greater movement of lymphatic fluid which transports white blood cells throughout the body and removes waste products, cellular debris, and bacteria.”

The Pro Extreme version of the tape has, according to Cassady, a stronger adhesive than some of the company’s other tapes. “It wasn’t a normal application for us,” she said. “Ordinarily, we shouldn’t put it over stitches. It comes in precut 10-inch strips, and [Brady’s] was cut in half. Typically, we would use all of it and wrap it around the wrist so it wouldn’t peel.”

Although some of its tapes are made entirely of cotton fibers, other tapes are made of a “highly engineered, ultra-durable synthetic fabric with 30 percent stronger elastic cores. Both the cotton and synthetic materials create unidirectional elasticity which allows the tape to stretch in length but not in width. As a result, the elastic fibers provide stable support without restricting range of motion like a traditional rigid athletic tape.” It also allows for moisture release.

Like everyone at KT Tape after the game, Terris was pleased that the company’s logo was visible on the inside of Brady’s hand. And it was helpful for a 40-year-old quarterback who suffered a bad cut at a bad time.

As Cassady put it, “all of it aligned.”

For the doctor’s assistant, it was a kick to turn on the game and see it.

“When I saw it I was — ‘We were there,'” Chavarria said. “It was a lot of fun to see that, and Dr. ElAttrache was happy that it did work.”

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