Tom Brady Steps Into Under Armour

New England Patriots quarterback Tom Brady won his 100th game as an NFL quarterback on Monday night against the Dolphins wearing something different on his feet: Under Armour.

Tom Brady
Tom Brady

Sources say Brady's deal with Nike is up and Brady's camp had been talking with Under Armour.

As part of that discussion, he was fitted and was sent shoe samples. And although UA executives are mum, CNBC has learned that the fact that Brady wore the shoes in a game has now accelerated talks. Brady's agent Steve Dubin did not return a call seeking comment.

The Under Armour logo was visible on Brady's shoes for the matchup against the Dolphins, which is unusual, not only because a deal isn't done, but Brady typically puts so much tape on his shoes and around his ankles that you normally can't see any logo. Shoe brands who pay athletes typically look down on the practice known as spatting.

Brady's endorsement could be a nice boost for the Under Armour brand, which has suddenly shifted focus from signing defensive players to offensive weapons. The company's last two NFL signees included Baltimore Ravens wide receiver Anquan Boldin and Dallas Cowboys wide receiver Miles Austin.

Brady was featured in a series of Nike commercials, but he hasn't been a focus for the brand for a while as the company has focused on the likes of Adrian Peterson and Troy Polamalu.

Brady signed a four-year, $72 million contract that included $49 million in guaranteed money last month. Brady's endorsements include Coca-Cola's Smartwater , Movado watches and Comcast .

Despite its recent struggles to stay relevant in the footwear space — Under Armour is launching its first basketball shoe line in less than three weeks — investors are bullish on the $1 billion company. Shares of its stock are up 65 percent year to date. (Track All Under Armour News and Stock Moves Here)

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