Bill Belichick believes the kicking footballs used during the first half of Sunday's loss by the New England Patriots against the Kansas City Chiefs were "under inflated by 2, 2 1/2 pounds."

"We don't have anything to do with it. Were we aware of it? Yeah, definitely," Belichick said. "As I understand it, they were all the same. I don't know what the explanation is. It was the same for both teams.

"You'd have to talk to the league about what happened on that. That part of it, they control all that."

Per league rules, the kicking footballs are supposed to be between 12.5 and 13.5 pounds per square inch, with officials in charge of ensuring that is the case as they are in possession of all footballs leading up to the game.

Belichick said missed field goals by Kansas City's Harrison Butker (39 yards) and New England's Chad Ryland (41 yards) in the first half, and two kickoffs that almost went out of bounds, were plays in which "you could see" how the underinflated footballs affected the game.