As the Los Angeles Rams begin to prepare to defend their title, it's worth noting just how quickly some of the NFL's former champions lost their luster.
Even the very best have gone from heroes to zeros in the space of just a single season, such is the unforgiving nature of the NFL.
Joe Montana and the 82' Super Bowl champion San Francisco 49ers began the defence of their first title to a backdrop of simmering tension between the players' union and the NFL.
The Niners were 0-2 after a couple of close but sloppy defeats to the Los Angeles Raiders and Denver Broncos when the players, unhappy with the inequities of money distribution and opaque salary structures, went on strike.
When it ended 57 days later, the champions were facing a major uphill battle to make the playoffs in what would be a nine-game regular season.
Montana threw for three touchdowns and more than 400 yards in a much-needed 30-21 victory over the St Louis Cardinals, but the Niners' defense was still off-key and it showed in a 23-20 loss to New Orleans a week later.
Their most shambolic outing of that ill-fated campaign came at home to the San Diego Chargers, which turned into a shootout that not even Montana and legendary All-Pro receiver Dwight Clark could keep them in, and the final game of the shortened season was rendered meaningless.
The Denver Broncos' chances of making the playoffs, let alone achieving a third straight Super Bowl success, took a nosedive when legendary quarterback John Elway announced his retirement.
So expectations were anything but mile high when head coach Mike Shanahan opted to send untested second-year QB Brian Griese into the huddle over veteran back-up Bubby Brister.
Denver made a disastrous start, going 0-4 through the first month of the season, and losing star running back Terrell Davis - the reigning league MVP - and future Hall of Fame tight end Shannon Sharpe to season-ending injuries.
Their eventual 6-10 record, featuring the most losses for a defending Super Bowl champion, is still the worst ever for a Lombardi Trophy defence in a non-strike season.
Elway's absence - and particularly his fourth-quarter heroics - was keenly felt as the Broncos lost eight of those games by one score.
A few months removed from leading the Oakland Raiders to Super Bowl XV glory, quarterback Jim Plunkett was benched in favour of 1980 first-round draftee Marc Wilson after three straight shutout losses early in the season - an NFL record.
Tom Flores' team finished with a 7-9 record and became only the fourth defending champion in NFL history to miss out on the playoffs.
Wilson threw 19 of the team's 28 total interceptions over the season as the passing offense ranked 26th of 28 teams.
And, after the Raiders' defense had led the NFL in interceptions and takeaways in 1980, they finished dead last in this category as defending champion - leading to a -16 turnover differential.
One fateful decision early in 1991 probably changed the course of modern football history as New York Giants general manager George Young passed over defensive coordinator Bill Belichick.
He instead promoted Ray Handley, the team's running backs coach, to head coach after Super Bowl winner Bill Parcells announced his retirement.
Back-to-back mid-season losses to NFC East rivals Washington and Philadelphia put New York under .500 and, despite a three-game rally, they lost three of their last four regular-season games to finish 8-8 and miss out on the playoffs.
The Giants lost much of their defensive muscle following Belichick's defection to the Cleveland Browns after missing out on the top job, while Handley's decision to play long-time back-up Jeff Hostetler over two-time Super Bowl winner Phil Simms at quarterback for much of the season seemed a strange one.
After Jerome 'The Bus' Bettis announced he was retiring after a customary post-Super Bowl trip to Disney World, there was a leadership void in the Pittsburgh Steelers' locker room.
Then came Ben Roethlisberger's off-season motorcycle crash and emergency appendectomy as the defending champions looked rudderless in the first half of the 2006 season.
Big Ben finished with a league-high 23 interceptions and - after starting 2-6 - Pittsburgh could not recover in an underwhelming 8-8 season which saw them finish second in the AFC North and miss the playoffs for the first time since 2003.
Bill Cowher retired after the season, but the Steelers were able to bounce back quickly under new coach Mike Tomlin - making the playoffs in 2007 and winning their sixth Super Bowl a year later.