13. Miami Dolphins (1972)
The Dolphins remain the only undefeated team in NFL history. They went through the entire 1972 season without suffering a single defeat. It was a glorious achievement and one that the franchise is proud of. Don Shula guided the team to a Super Bowl win over the Redskins. The old mantra says that defenses win titles. This was exactly the case for the Dolphins because it was magnificent (via Sportscasting).
Bob Griese broke his ankle about midway through the season, but he returned for the postseason. This was crucial too because he was a reliable pair of hands. The Patriots almost emulated their winning year in 2008 but they fell short at the end. Furthermore, the Dolphins almost became the first team to go 0-16 in 2007.