In the last 10 years, 18 teams have been unbeaten and untied in preseason play. Those teams went on to post a combined regular-season record of only 130-158.
The teams that were perfect in the preseason also did not improve from the previous season, declining by a total of 23½ games, dropping more than one win per team.
In some cases, a good preseason did herald a successful year. The Broncos parlayed a perfect preseason in 2005 into a 13-3 record, and the 2013 Seahawks won the
Super Bowl after a 4-0 preseason.
But more often, the preseason wonders flopped when the games started to count. In 2013, the Redskins, who had won 10 games the previous season, fell to 3-13. The 2011 Rams won all four games in the preseason, then went on to win just two regular-season games.
The most egregious case was the 2008 Lions. They swept through the preseason, outscoring their four opponents by 80-32. Among their victims were the Giants, who would go 12-4 that year.
The Lions fell apart in the regular season. Trying out Jon Kitna, Dan Orlovsky and Daunte Culpepper as starting quarterbacks, Detroit staggered to the league’s first 0-16 record.
In contrast to the summertime highfliers, eventual Super Bowl champions generally had undistinguished preseasons. Even with the 2013 Seahawks’ 4-0 record, the winners of the last 10 Super Bowls have posted a combined preseason record of only 23-17.