The 1972 Miami Dolphins

The team wasn't especially big, quick, or flashy. It rarely blew away opponents. Its best player was a fullback, its defense was anonymous, and it played without its Pro Bowl quarterback for most of the year. Still, the 1972 Miami Dolphins are the only team to finish a season undefeated -- 17-0, to be exact -- in National Football League history. Fresh off a Super Bowl loss the season prior, Miami played like a team determined to win a championship, racking up 14 straight regular season wins. The Dolphins offense relied heavily on their ground game, running the ball 613 times and boasting the first pair of 1,000-yard runners in Larry Csonka and Mercury Morris. On the other side of the ball, the "No Name Defense" was no less dominant, giving up the fewest points in the league. Then, in the postseason, Miami enjoyed the return of quarterback Bob Griese, who was sidelined most of the season due to leg and ankle injuries. In Super Bowl VII, Griese threw a 28-yard touchdown pass to Howard Twilley for the game's first score before a few scares by George Allen's Redskins threatened the Dolphins' bid for an unbeaten year.