text: The Cowboys began the 1977 season 8–0 before losing in consecutive weeks to the St. Louis Cardinals in a Monday night home game and the Steelers in Pittsburgh. After the losses, however, the Cowboys won their final four regular season games. Dallas had both the #1 defense and #1 offense in the NFL. In the postseason, the Cowboys routed the Chicago Bears 37-7 and Minnesota Vikings 23–6 before defeating the Denver Broncos 27–10 in Super Bowl XII in New Orleans.  As a testament to Doomsday's dominance in the hard-hitting game, defensive linemen Randy White and Harvey Martin were named co-Super Bowl MVPs, the first and only time multiple players have received the award.
  1978: Fifth Super Bowl appearance
  After a slow start in 1978, Dallas won its final six regular season games to finish the season at 12–4. After an unexpectedly close divisional playoff game against the Atlanta Falcons at Texas Stadium, the Cowboys traveled to Los Angeles and shut out the Rams in the NFC Championship Game 28–0 to return to the Super Bowl.  In Super Bowl XIII, Dallas faced the Steelers at the Orange Bowl in Miami. The Steelers outlasted the Cowboys 35–31, despite a furious comeback that saw Dallas score two touchdowns late in the fourth quarter. The game was not decided until the final 22 seconds, when a Dallas onside kick failed.  Bob Ryan, an NFL films editor, dubbed the Cowboys "America's Team" following this season.