The roots of the icy Jim Harbaugh-Pete Carroll relationship date to their days as college coaches, well before they got to the NFL.
Carroll built up a powerhouse at Southern California, but cracks started to show after Harbaugh got to Stanford. The Cardinal pulled off an upset of the Trojans in 2007 when Stanford was a 41-point underdog.
Two years later, Stanford went for a two-point conversion late in a 55-21 win against USC. Afterward, Carroll and Harbaugh met at midfield for a chilly and short conversation. See it below: