The event was also notable for having the shortest WrestleMania match Competition ever , when The Rock beat Erick Rowan , in an impromptu match , the unannounced appearance of John Cena , and the André the Giant Memorial Battle Royal , which included Cause_to_be_included the surprise participation of NBA legend Shaquille O'Neal and was won by NXT call-up Baron Corbin in his main roster debut Process_start .