sentences:  It was the thirteenth Indy 500 sanctioned by the Indy Racing League, and served as the showcase event of the 2008 IndyCar Series in DIRECTV HD season.It was the fifth round of the 2008 IndyCar Series season.It was the first Indy 500 after the open wheel "unification" took place, and it featured a full complement of entries of IndyCar Series regulars, as well as former Champ Car teams.