Tom Brady is switching teams.

The New England Patriots superstar quarterback recently signed an endorsement deal with Under Armour after his apparel contract with Nike expired last summer.

"Under Armour's everything I was looking for,'' Brady said. "It's cool. It's fun. It's what so many of the kids are wearing, and I like to try to stay cutting-edge. I like the company. I think we've got a lot in common. We both want to stay hungry, stay humble.''

Brady is the first superstar quarterback to sign with Under Armour, the 14-year-old Maryland outfitter that is one-20th the size of Nike. He will appear in Under Armour commercials and print ads starting early in 2011.

Brady is not only joining Under Armour as a contracted endorser, but also is getting a financial stake in the company. "Tom is a shareholder in Under Armour,'' said 38-year-old company founder and CEO Kevin Plank. "Equity was a part of our deal. That was important to Tom, that [a stake in the company] was a part of the deal.''

Brady joins Ray Lewis, Michael Phelps and Lindsey Vonn as the biggies in Under Armour's stable.

"At this point in my career, it's got to be about a product I believe in," Brady said. "I felt there wasn't anything better out there. This is such a young company to be where they are. This kind of tells you where the market's at.''

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