In 1972, when the regular season consisted of just 14 games, Don Shula's Miami Dolphins became the first team of the modern NFL era to win it all, going 17-0. Since the introduction of the 16-game season in 1978, the benchmark has been set by the 2007 New England Patriots, led by quarterback Tom Brady, with an unbeaten regular season followed by two play-off victories.
But complete perfection eluded the overwhelmingly favoured Patriots, who lost Super Bowl XLII in the cruellest fashion, going down by just three points when the New York Giants scored the go-ahead touchdown with just 35 seconds remaining.
The current Packers are uncannily similar to the 2007 Patriots. Count the six successive regular season and play-off wins at the end of 2010 and they are already on a 17-game unbeaten streak. Both teams score seemingly at will; Green Bay currently average 35 points a game, close to New England's record 37 points-per-game haul four years ago.
Statistically, the Packers' defence leaves something to be desired (although even that can partly be put down to the loss of star safety Nick Collins to injury). But in gridiron, like every other team sport, if you score more than the opposition you win. The defence, moreover, has more than made up for its positional frailties by leading the league in interceptions.
"I don't believe anyone is going to beat the Green Bay Packers, I don't know of a way to beat the Packers," says Michael Irvin, TV analyst and star receiver on the Dallas Cowboy team that was as dominant in the early 1990s as the Packers are now. Tony Dungy, who coached the Indianapolis Colts to a 13-0 start in 2005, agrees. "I think they are going to go undefeated."
Green Bay's ultimate weapon is Aaron Rodgers. Great quarterbacks make great football teams, and Rodgers is having a season to rival, perhaps exceed, Brady's record-breaker of 2007.
His figures through 11 games are on course to put him alongside not only Brady and his own Packers predecessor Brett Favre but the supreme NFL quarterbacks of any era. Thus far, Rodgers has thrown for 3475 yards and 33 touchdowns, and surrendered just four interceptions. His pass completion rate of nearly 72 per cent, if sustained, would be an all-time NFL record.
He is on track to be only the third quarterback, after the legendary Dan Marino, and Drew Brees of the 2008 New Orleans Saints, to register a 5000-yard season, and could yet beat the single season touchdown record of 50, thrown by Brady in 2007. As for Rodgers' passer rating - the most comprehensive measure of a quarterback's performance - it stands at an unheard-of 127.7.
But numbers tell only part of the story. The most mesmerising moment in all American sport right now is watching a Packers snap back from the line of scrimmage, and Rodgers in the "hole" wheeling, feinting and probing - before delivering a telepathic inch-perfect pass to a receiver who has found a gap that a split-second earlier did not exist. Every time the Packers gain possession, they look like scoring.
Even in the comparatively short NFL regular season, invincibility is something very special. In 39 years, only the Patriots have managed it, though five teams have gone 15-1. Year after year, an all-conquering team lose end-of-season games when divisions are already won, and home field advantage in the playoffs is already secure.
Sometimes it is lack of motivation, sometimes a desire to protect key players from injury. The Packers need just one more win to wrap up their division, and only two more to be top seed in their conference. If they faltered in a meaningless game thereafter, they would not be the first team of destiny to do so.
A first test comes on Monday (NZT) when they face the ever-dangerous New York Giants on the hostile territory of the MetLife Stadium, whose treacherous winds could betray even the laser bullets fired by Rodgers' arm. Then the Packers must meet their bitterest divisional rivals, the Chicago Bears and the Detroit Lions, albeit back in familiar, frigid Green Bay.
"We're getting better every week," says Rodgers, but he avoids mention of the unmentionable. "I think we're a long way from there [perfection]. But if we're fortunate enough to be still undefeated after 14 or 15 games, maybe we can start talking about what you were talking about."
- Independent