Amid an NFL investigation into whether the New England Patriots intentionally deflated footballs during the AFC Championship game, quarterback Tom Brady said he did nothing to change the pressure.

“I didn’t alter the ball in any way,” Brady said at a news conference Thursday, hours after head coach Bill Belichick said he did not know how the footballs were deflated.

Brady said he handled the footballs hours before the game and did not know what happened in the hours in between.

He said NFL investigators had not spoken to him yet.

During the news conference, Brady was asked if he was a cheater. “I don’t believe so,” he said. “I feel like I’ve always played within the rules, I would never do anything to break the rules.”

The rules said footballs should be inflated to at least 12.5 psi. Reports said 11 of 12 footballs used in the first half of the AFC Championship were substantially softer.

Brady said he goes through a process breaking in footballs because he wants to be familiar with the equipment he uses. He said he has no thought of the football once he’s out on the field playing.

“I can’t do anything about what happened. I can only do something going forward,” he said.

Brady said he did not notice the balls were underinflated and that he did not notice the change to the second half.

“Once I approve the ball, that’s the ball I expect out there on the field,” he said.

Whether anyone let air out of the balls, Brady said he was unaware of any tampering.

“I’m very comfortable saying that nobody did it, as far as I know,” Brady said. He said later he did speak to his teammates Thursday morning, but that he wanted to keep that within the team.

Brady said he felt the Patriots won the game fair and square and were now focusing on facing the Seattle Seahawks in the Super Bowl on Feb. 1 in Glendale, Ariz.

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