It was some combination of religion, a grudge involving Knute Rockne and a rival, and maybe the simple time-honored notion that some people just don’t like Notre Dame.

For the first time in 17 years, Notre Dame and Penn State are set to face off on a football field. This time, there's a lot on the line, as the 7-seed Fighting Irish will play the 6-seed Nittany Lions in the Orange Bowl,

The first College Football Playoff semifinal will feature Penn State and Notre Dame. A breakdown of the keys to victory in the Orange Bowl.