From CBSSports.com  Brady on Deflated Footballs"

Patriots quarterback Tom Brady in his Monday morning appearance on the New England radio station WEEI, called the report, "ridiculous." Brady laughed and said, "I think I've heard it all at this point. That's the last of my worries. I don't even respond to stuff like this." We'll obviously see how this shakes out, but Brady doesn't seem too broken up about it."

This is not a good denial (and I'm a Tom Brady fan).  Poor denials (or even better none at all) lend credibility to the allegation.