 It was also commonplace for division opponents to play each other in the preseason, due to the larger size of pre-merger divisions, but has not happened since 2000, when the Seattle Seahawks played the Oakland Raiders.As recently as 1984, the Cleveland Browns and Pittsburgh Steelers played a preseason game despite the two being bitter rivals.In 1999 the San Diego Chargers played their division rivals the Denver Broncos and Kansas City Chiefs in the preseason.