Just prior to the start of the game. Timing still makes it hard to figure out how they would tamper with them after that. I'm sure the Pats are loving this. It's the kind of mind game that will give the Seahawks pause.
The attendant need only keep a ball needle in his pocket and insert it into the ball bladder for a couple of seconds to let some air out when everyone has their eyes on the game.
The Gaylord Perry effect