The 1984 San Francisco 49ers (15-1) are one of four teams to lose just a single game in the regular season since the NFL expanded its schedule to 16 games in 1978. After six straight victories to open the season, the 49ers lost their first in Game 7 and didn't lose again, finishing 18-1 overall and beating Miami 38-16 in Super Bowl XIX. (Photo by George Rose/Getty Images)

Regarded as the greatest team in the NFL history, the 1985 Chicago Bears (15-1) was the first team in the 16-game era to start a season 12-0 (three teams have done it since, including New England this year). They would lose Game 13 at Miami, but that was their final defeat. They dominated their three postseason games, shutting out the Giants and Rams in the NFC playoffs, and crushing New England 46-10 in Super Bowl XX. (Photo by George Rose/Getty Images)

The 1998 Minnesota Vikings, behind a high-powered offense featuring QB Daunte Culpepper and WR Randy Moss, finished 15-1 in the regular season. They lost for the first time in Game 8, then ripped off eight more wins to secure homefield advantage. However, after beating Arizona in a divisional playoff game, Minnesota couldn't get past Atlanta, losing 30-27 in the NFC Championship Game. Photo by Scott Halleran /Allsport

In the first season of the 16-game schedule, the 1978 Pittsburgh Steelers (14-2) finished with just two losses – the first coming in Game 8 and the second in Game 11. They would not lose again that season as they ripped through the playoffs, beating Dallas 35-31 in Super Bowl XIII.

The 2004 Pittsburgh Steelers finished 15-1. But unlike the previous two teams in the 16-game era to lose just once in the regular season, the Steelers lost their game early, falling in week 2, before winning 14 straight. They would make it 15 in a row with a divisional playoff win over the Jets, but fell short of the Super Bowl when they lost 41-27 to New England in the AFC Championship Game. (Photo by Rick Stewart/Getty Images)

Who knew the Washington Redskins (14-2) would lose just two games in the 1983 regular season after they opened with a loss at home to Dallas? They would lose their second in Game 7, to Green Bay in one of the most memorable Monday night games (48-47), but that would be their last defeat … until Super Bowl XVIII, when they came in as huge favorites but were steamrolled by the Los Angeles Raiders 38-9. (Photo by Al Messerschmidt/NFL)

The 1984 Miami Dolphins (14-2) started the season with 11 straight victories, before losing twice in three games. A prolific scoring team, the Dolphins easily got through the AFC playoffs with victories over Seattle and Pittsburgh, before losing to the 15-1 San Francisco 49ers 38-16 in Super Bowl XIX. It was the first time that season the Dolphins had been held under 21 points. (Photo by NFL/NFL)

The 1986 Chicago Bears (14-2), one year removed from a one-loss season, won their first six before losing two out three at midseason. They won their next seven, but were surprised by the Washington Redskins in a divisional playoff game, 27-13. (Photo By Manny Rubio-US PRESSWIRE)

The 1986 New York Giants (14-2), like the '83 Redskins, lost their first game to Dallas, lost again in Game 7, but didn't lose again the rest of the way. Not in the regular season or the playoffs. Lawrence Taylor's Giants beat down John Elway's Denver Browns 39-20 in Super Bowl XXI. (T. G. Higgins /Allsport)

The 1989 San Francisco 49ers (14-2) spread their two defeats around, losing Games 4 and 11. Their Game 11 loss to Green Bay would be their last as they cruised in the playoffs, outscoring their three opponents 126-26, including 55-10 over Denver in Super Bowl XXIV. (Photo by George Rose/Getty Images)

The 1990 San Francisco 49ers (14-2) didn't lose their first game until they had already 10 victories under the belts. They lost a 13-10 defensive battle to New Orleans in Game 15 and another to the New York Giants in the NFC Championship Game, 15-13. (Photo by Mike Powell /Allsport)

The 1991 Washington Redskins (14-2) won 11 straight to open the season before losing to Dallas at home in Game 12. With homefield advantage wrapped up, the 49ers rested their starters in Game 16, which they lost 24-22 at Philadelphia. The rest must have helped: They laughed their way through the playoffs, beating Buffalo 37-24 in Super Bowl XXVI. (Photo by Jonathan Daniel /Allsport)

The San Francisco 49ers entered the 1992 season having gone 14-2 in back-to-back campaigns. They made it three straight, accomplishing it in a different manner, however. In the previous two seasons they had ripped off 10 and 11 wins to start the season, but in 1992, they lost in Games 2, and again in Game 8, before a perfect second half. A wet blanket was thrown on an otherwise brilliant season when Dallas defeated San Francisco in the NFC Championship Game 30-20. (Photo by Stephen Dunn /Allsport)

The 1998 Atlanta Falcons (14-2) surprised everyone by losing just twice in the regular season – in Games 3 and 7. Dan Reeves' Dirty Bird squad used its powerful offense and a stingy defense to get all the way to Super Bowl XXXII, where it lost to a Denver team that lost only twice as well 34-19. (Photo by Andy Lyons / Getty Images)

The 1998 Denver Broncos (14-2) started the season with 13 straight victories before losing back-to-back road games to the Giants and Dolphins. The next time they played on the road was in Super Bowl XXXII, where they beat the 14-2 Atlanta Falcons 34-19. (Photo by Tom Hauck /Allsport)

Four years removed from being an expansion team, the 1999 Jacksonville Jaguars (14-2) used a dominating defense to lose only twice in the regual season – both to Tennessee in Games 3 and 15. Unfortunately for the Jaguars, the Titans showed up on the schedule a third time – in the AFC Championship Game, where Jacksonville fell again, 33-14. (Photo by Andy Lyons /Allsport)

Kurt Warner and the 2001 St. Louis Rams (14-2) lost for the first time in Game 7, then again in Game 10. The next defeat for The Greatest Show on Turf came in Super Bowl XXXVI, where the Rams fell to New England 20-17. (Photo by Elsa/Allsport)

The 2003 New England Patriots (14-2) got their losses out of the way quickly, going down in Games 1 and 4. Fifteen wins later, they were crowned NFL champions, beating Carolina 32-29 in Super Bowl XXXVIII. (Photo by Rick Stewart/Getty Images)

Not to be outdone by their 2003 team that finished 14-2 and won the Super Bowl, the 2004 New England Patriots duplicated the feat. But instead of their losses coming early in the season like in 2003, the '04 Patriots didn't lose their first until Game 7, then again in Game14. They won easily in the AFC playoffs before getting a fight from Philadelphia in Super Bowl XXXIX, where they beat the Eagles 24-21. (Photo by Eliot J. Schechter/Getty Images)

Peyton Manning and the 2005 Indianapolis Colts (14-2) became only the second team in the 16-game era to win their first 13 games. But they would lose back-to-back games to San Diego and Seattle, before winning the regular-season finale. They were shocked by Pittsburgh in a divisional playoff game, putting a damper on an otherwise special season. (Photo by Otto Greule Jr/Getty Images)

Last year, the 2006 San Diego Chargers (14-2) lost two of their first six games, then ripped off 10 straight victories to close the regular season. With momentum on their side, the Chargers laid an egg in the playoffs, losing to New England 24-21 at home in what would turn out to be Marty Schottenheimer's final game as Chargers coach. (Photo by Lisa Blumenfeld/Getty Images)