Tom Brady's private quarterback coach, Tom House, believes mechanics were an issue for some of his 2013 struggles.

Brady had a 60.5 completion percentage, 4,343 yards, 25 touchdowns and 11 interceptions while throwing to a limited set of targets.

“As he's getting a little older you lose a little strength, you lose a little flexibility,” House said, via the Boston Globe. “And what was happening was he was noticing that his accuracy and his long ball weren't what they were three or four years ago. So we ran him through the computer, compared him to the models we have created for movement efficiency, and there were really, really small things that were causing his issues."

Brady and the Patriots advanced to the AFC Championship Game.

“One of the things that we've learned about quarterbacking -- it's not the length of the stride, it's the timing of the stride. Tom is long and lanky,” House said. “If Tom has an issue, he gets a little long. ... That's one of the things that we focus on when we analyze Tom every year and we maintain during the season, is how quick does he get into the foot stride?"