(Editor's note: The following is an updated version of a story originally published on ESPN.com in January 2008.)

New England Patriots quarterback Tom Brady enjoyed a 2007 regular season so dominant that he made us ponder how his performance stacked up against the greatest years in the history of the league. Five years later, Minnesota Vikings running back Adrian Peterson is doing the same thing, inspiring us to update our list of the 10 greatest individual seasons in NFL history.

How do we determine the best individual years ever in the NFL? Some people think it all comes down to the players who possess the best numbers. Others view context as being more critical, especially when some players -- such as O.J. Simpson and Jerry Rice -- set their records in fewer games than the players who broke them.

So here's what we think about the matter of which players enjoyed the greatest seasons since the AFL-NFL merger in 1970. We're sure you'll have your own opinions:

At age 24, Eric Dickerson averaged 5.6 yards per carry and 131.6 yards per game in 1984. David Madison/Getty Images

1. Dan Marino, Miami, 1984: Marino used his second NFL season to terrorize opposing defenses on a weekly basis. Blessed with a quick release and a rocket right arm, he produced a season-long performance that required its own section in the league record books once he was done. Marino set NFL marks for yards (he became the first player to pass for 5,000 yards in a season with 5,084) and touchdown passes (he blew away the old mark of 36 with 48 of his own) and he led the Dolphins to a spot in that season's Super Bowl. Marino's Hall of Fame career included many great seasons, but nothing ever topped those feats.

In fact, there is one chief reason his performance still ranks better than those produced more recently by Peyton Manning and Brady:

The application of the rules was different. Both Manning and Brady benefited from the league's decision in 2004 to place greater emphasis on enforcing the illegal contact rule, which penalizes defenders who touch receivers more than five yards beyond from the line of scrimmage. If Marino had that advantage going for him, nobody would've ever matched the season he produced 24 years ago.

2. Eric Dickerson, Los Angeles Rams, 1984: All you have to know about Dickerson's record-breaking season -- he gained 2,105 rushing yards that year -- is that the Rams didn't have much of a passing game. Their offense hinged primarily on Dickerson's running right, Dickerson's running left and Dickerson's running just about everywhere else in between. That he generated so much yardage is a testament to the men who blocked for him and the remarkable skills he was blessed with. The man was one of the best pure runners the NFL has ever seen.

Some skeptics complain that Dickerson needed 15 games to reach the 2,000-yard mark -- while O.J. Simpson did it in just 14 games back in 1973 -- but Dickerson was both spectacular and steady. As proof, just consider that Dickerson set a record that year by eclipsing the 100-yard mark 12 times that season. You don't do that by getting extra touches. And you don't hold the record for rushing yardage as long as Dickerson has without doing something truly special.

3. Adrian Peterson, Minnesota, 2012: Even if Peterson doesn't surpass Dickerson's record, he's put together a season for the ages. No running back has done what he has done with so many factors working against him: the surgically repaired knee, the lack of offensive weapons around him, the inconsistency of a passing game led by a second-year quarterback. Just getting close to the 2,000-yard mark with all those challenges tells you the man has accomplished something we may never see again. Through 15 games, Peterson is averaging 6.0 yards per carry and 126.5 yards per game.

4. Peyton Manning, Indianapolis, 2004: Only one quarterback in NFL history -- Green Bay's Aaron Rodgers in 2011 -- has ever been more efficient over a full season as Manning was during this campaign. Yes, Manning's season is remembered mostly because he threw a then-record 49 touchdown passes. But another league mark that Manning broke that season -- his passer rating of 121.1 easily eclipsed the former record of 112.8 set by former 49ers quarterback Steve Young in 1994 -- was just as remarkable. It basically meant that Manning didn't have a performance that was less than excellent all season. (Rodgers went on to break Manning's record with a 122.5 rating in the pass-happy 2011 season.)