When Chip Kelly was Oregon's head coach from 2009 through 2012, the word got out pretty quickly: Kelly's thoughts on conditioning and sports science had his team more ready than the opponent to play for a full 60 minutes, and when you played the Ducks, the second half would be a real problem as Kelly directed his quick-strike offense against your tired and out-manned defense.
That very nearly happened to the Atlanta Falcons in their season-opening win against Kelly's Philadelphia Eagles, who roared back from a 20-3 halftime deficit to make the 26-24 final a lot more interesting that Atlanta would have liked.