Super Bowl XIX was played between the San Francisco 49ers and a team the year before lost to which team in the playoffs?
Super Bowl XIX: Super Bowl XIX was an American football game between the American Football Conference (AFC) champion Miami Dolphins and the National Football Conference (NFC) champion San Francisco 49ers to decide the National Football League (NFL) champion for the 1984 season. 1984 Miami Dolphins season:  The Dolphins sought to build on a spectacular 1983 season where they went 12–4 with rookie quarterback Dan Marino, only to be upended by the Seattle Seahawks in the playoffs.
Seattle Seahawks