Trailing 14-6 at halftime, the Chiefs took the second-half kickoff and marched from their 25 to the Patriots’ 40. On second-and-8, running back Knile Davis took a pass from quarterback Alex Smith and ran for what would have been a first down. But Davis fumbled on his way to the ground and New England recovered. Five plays later, the Patriots led 21-6 on a 16-yard touchdown pass from Tom Brady to Rob Gronkowski. That fumble was the lone turnover and proved costly as New England moved on to its fifth consecutive AFC championship game.