In 2007, Belichick led the Patriots to the first perfect regular season since the introduction of the 16-game regular season schedule in 1978, only the fourth team to do so in National Football League history after the 1934 and 1942 Chicago Bears and 1972 Miami Dolphins. In the of the playoffs, they defeated the Jacksonville Jaguars by a score of 31–20. In the , the Patriots defeated the San Diego Chargers by a score of 21–12. The Patriots were upset in Super Bowl XLII by the New York Giants, his former team, due to the defense allowing a famous play to David Tyree near the end of regulation The Patriots' failure to attain a "perfect season" (undefeated and untied, including playoffs) preserved the Miami Dolphins as the sole team to do so, having finished their 1972 regular season at 14–0 and having won three games in the playoffs. Only two other teams in professional football have recorded a perfect season—the 1948 Cleveland Browns (14–0) of the then All-America Football Conference and the 1948 Calgary Stampeders (12–0) of the Canadian Football League. No team in the former American Football League had a perfect season.