In the NFL world, nobody's perfect. Well, except for one.

Many have tried and even more have failed in their quest to capture an undefeated season in the league. Based on the small number of games played, it's the easiest of the major American sports leagues to accomplish but it remains a nearly impossible task.

As the saying goes, any team can lose on any given Sunday, leaving countless things to chance.

Between turnovers, injuries, penalties, weather and other factors that are more player-specific, it all leads to at least one loss every season.

As one team found out, getting through the regular season with an undefeated season practically means nothing if you don't finish the job with a Super Bowl victory.

Just two teams have made it through the NFL regular season with an undefeated record. Only one has been able to win the Super Bowl. Here's a look at the two clubs.

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What is the only NFL team to go undefeated in a season and win the Super Bowl?

The 1972 Miami Dolphins remain the only NFL to complete a perfect season.

Others have come close but haven't been able to finish the job. The remaining living members of the team famously get together every year to celebrate the last undefeated team's loss in the regular season – preserving their streak.

The path to an undefeated season has only gotten harder over the years. With the addition of regular season games to the schedule, teams now have to go 20-0 to make history. Miami only needed 17 wins to accomplish that feat, emerging victorious in all 14 regular season contests and the three playoff games.

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How many NFL teams have gone undefeated in the regular season?

Only two teams in the Super Bowl era have gone undefeated – the 1972 Dolphins and the 2007 New England Patriots.

New England won all 16 regular season games and their first two playoff games before falling to the New York Giants in Super Bowl 42. It's a game widely regarded as one of the biggest upsets in NFL history.

The 2007 Patriots' 18-1 record is tied for the most wins in a single season in NFL history. They are joined by the 1985 Chicago Bears and 1984 San Francisco 49ers.

Those three teams will be joined by the winner of Super Bowl 59 as both the Philadelphia Eagles and Kansas City Chiefs enter the game with 17 wins.

This article originally appeared on USA TODAY: NFL undefeated seasons: Has a team ever had a perfect record?