The NFL has one of the most competitive postseasons in all of sports. Its one-and-done format is different than that of the major sports in the country and sets up the possibility for true underdog stories to emerge.
Over the course of the NFL's history, there have been plenty of monumental upsets. Fans have learned that teams that are heavily favored are never safe from potentially blowing a game at the worst possible time, not even in the postseason.
That's why the NFL's "any given Sunday" mantra is more than just a cliché.
Still, the anatomy of an upset gets at least a bit more difficult in the playoffs. True juggernaut teams are hard to defeat, so there isn't an overwhelming amount of big-time upsets.
But still, there have been more than a handful of times that postseason teams have gone into games as shoo-in winners only to exit them as surprise losers. Here's a run down of some of the NFL's most shocking postseason results.
MORE: How one Jets play fueled a history-altering upset in Super Bowl III
Biggest upsets in NFL playoff history
The NFL has had plenty of big-time upsets in its history, but only nine times have underdogs of 11-plus points won an NFL playoff game outright.
The biggest upset came back in 1969 when the Joe Namath-led Jets beat the Colts in Super Bowl 3. It had been presumed that the Colts, hailing from the NFL, would easily dispatch the Jets, who came from the AFL. Instead, the upstart league got a big win over the NFL shortly before the two operations merged.
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Arguably the most notable double-digit underdog to win outright is the Giants. New York beat the Patriots 20-17 in Super Bowl 42 to deny previously 18-0 New England a perfect season, which had previously been achieved by only the 1972 Dolphins. New England was a 12.5-point favorite in that contest.
Below is a look at the biggest upsets in NFL playoff history, according to spreads from Stathead.
| Matchup | Date | Round | Spread | Winner |
| Jets vs. Colts | Jan. 12, 1969 | Super Bowl 3 | Colts -18 | Jets, 16-7 |
| Patriots vs. Rams | Feb. 3, 2002 | Super Bowl 36 | Rams -14 | Patriots, 20-17 |
| Jaguars at Broncos | Jan. 4, 1997 | Divisional | Broncos -12.5 | Jaguars, 30-27 |
| Giants vs. Patriots | Feb. 3, 2008 | Super Bowl 42 | Patriots -12.5 | Giants, 20-17 |
| Chiefs vs. Vikings | Jan. 11, 1970 | Super Bowl 4 | Vikings -12 | Chiefs, 23-7 |
| Chargers at Colts | Jan. 13, 2008 | Divisional | Colts -11 | Chargers, 28-24 |
| Falcons at Vikings | Jan. 17, 1999 | NFC Championship | Vikings -11 | Falcons, 30-27 |
| Broncos vs. Packers | Jan. 25, 1998 | Super Bowl 32 | Packers -11 | Broncos, 31-24 |
| Vikings at 49ers | Jan. 9, 1988 | Divisional | 49ers -11 | Vikings, 36-24 |
Double-digit underdogs have a record of just 14-62 straight up in postseason history. Five of those 14 wins have been by underdogs of exactly 10 points.
