Complex sentence: Mega March Madness was a pay-per-view out-of-market sports package covering games in the NCAA Men's Division I Basketball Championship which was exclusive to DirecTV since 2002 and supplemented the coverage from CBS Sports.
Split into simpler sentences: Mega March Madness is a pay-per-view Out-of-Market Sports Package covering games in the NCAA Men's Division I Basketball Championship. It has been exclusive to DirecTV since 2002 and supplements the coverage from CBS Sports.