Rush Limbaugh just made a mistake (it doesn't happen very often). I think he just said that Lovie Smith and Tony Dungy are the first two professed Christian coaches to face each other in a Super Bowl.
... It happened at least once before: Redskins coach Joe Gibbs and Denver Bronco's coach Dan Reeves -- both professed Christians -- faced off in Super Bowl XXII.
Interestingly, this was also the fist Super Bowl to feature a black quarterback (Doug Williams).