Close your eyes.

Now visualize your personal video highlight reel -- a true YouTube -- of the 2010 NFL season. There are clips of ...

Tom Brady and other prolific passers are overshadowing running backs. Jason Miller/US Presswire

• Tom Brady's brilliance.

• Michael Vick's revival.

• Brett Favre's failings.

• Calvin Johnson's shoulda-been TD; Roddy White's wideout coming out.

• DeSean Jackson's Giant-killing punt return.

• Chicago's D, Tampa Bay's rise and Dallas' demise.

• James Harrison's shrinking wallet.

• Andre Johnson and Cortland Finnegan going all WWF on each other.

There are images of Matt Ryan, Drew Brees, Aaron Rodgers, Philip Rivers and, for worse or worse, Randy Moss (at least at the microphone).

And, oh yeah, snow pouring through the Metrodome roof.

It's quite a reel, but something's missing.

There's not a single clip of a dominant running back. No one breaking off rock-star runs like Tennessee Titans back Chris Johnson last season.

No one making DBs see "the light" like a healthy, tackler-crushing Adrian Peterson of Minnesota in previous years.

No one being slippery and smooth like the New York Jets' LaDainian Tomlinson in his prime.

This was the Year of the Quarterback (or at least the latest such year). Signal-callers claimed the game -- racking up highlights and yardage at a near-record pace -- and only stingily shared the spotlight with wide receivers, tight ends and a few lucky backs out of the backfield.

As a result, the dynamic, game-changing, game-dominating running back all but disappeared. Poof. Gone.

Opposing defenses and the Titans' woes dragged Chris Johnson's rushing totals down this season. Joe Robbins/Getty Images

Sure, the best teams -- the ones who can utter "Dallas" and "Super Bowl" without causing a snicker -- possess strong, reliable running games that set up and complement a steady yet explosive passing attack. But it's increasingly clear that teams can reach the Super Bowl without a strong, Jim Brown-like running back. In fact, since Texans running back Arian Foster is poised to lead the league in rushing yards per game this season (and Houston is long out of the playoff hunt), only two of the past 13 top rushers will have reached the Super Bowl (Shaun Alexander with the Seahawks in 2005 and Terrell Davis with the Broncos in 1998).

Overall, yards per carry across the league have remained steady in recent seasons: 4.21 in 2008, 4.24 in '09 and 4.21 so far this season. But the studs at the top have been decreasingly productive.

In 2000, the NFL's top five rushers averaged 101.3 yards per game. In 2005, the first five ran for 107.7 yards per game. So far this season, the league's five most "prolific" rushers -- Foster, Johnson, Kansas City's Jamaal Charles, Jacksonville's Maurice Jones-Drew and Atlanta's Michael Turner -- have produced an average of just 91.5 yards every outing. That's even a steep drop-off from last season, when the top five runners averaged 96.1 yards per game.

Opportunity isn't really to blame. Even in the Year of the QB, runners are getting their carries. Surprisingly, the league's overall run/pass percentage hasn't fluctuated as much as the rushing numbers might indicate. In 2000, teams ran on 43.8 percent of plays and passed 56.2 percent of the time. Last season it was 43.7 percent to 56.3 percent. So far in 2010, 44.6 percent of plays have been runs versus 55.4 percent passing plays.

So is 2010 an aberration or indicative of the new National Fling-it League?

"It's definitely been an unusual year," says Dennis Green, the former NFL head coach and current GM/head coach of the United Football League's Sacramento Lions. "But I think we're looking at the future."

The genesis of the evolution, says Green, came several years ago when some rule changes were introduced, including one that allowed offensive linemen more, uh, leniency in pass protection. "Guys can do almost anything except tackle the guy," says Green.

It may be mere coincidence, but in 2005, prior to the rule changes, offensive holding was called 880 times (and accepted 708). Last season, it was called on only 634 occasions (accepted 536). Hmm.

Along with the rule changes designed to protect the quarterback have come other alterations, all with one idea in mind: speed thrills.

Consider improved playing surfaces, more domes, further restrictions on manhandling wideouts and, of course, billion-dollar roofs. "Now, everybody thinks they can run fast," Green says with a laugh. "Even 320-pound linemen want to run fast."

Shaun Alexander (2005) is the last back to lead the league in rushing and reach the Super Bowl in the same season. Jonathan Ferrey/Getty Images

Here's another, more subtle change. Look at the shoulder pads of today's big guys -- the linemen and linebackers. Even defensive backs. Now Google the likes of linemen like Jack Kramer, Art Shell and Joe Jacoby; linebackers Dick Butkus, Mike Singletary and Lawrence Taylor; and defensive backs Ronnie Lott, Mel Blount and Lem Barney.

Compared with those of their predecessors, today's shoulder pads look like a couple of pairs of socks stuffed beneath the jerseys. "Big wide shoulders," says Green, "a little waist, big thighs and butt. That was the prototype lineman. Now, they're shaped straight up and down because their pads don't go outside their body."

The effect? Fewer bruising blocks in the trenches opening lanes for the likes of Gale Sayers, Barry Sanders, Emmitt Smith or even Peterson. "You can't hit without pads," says Green (it's also more difficult for defensive linemen to grab the small shoulder pads and toss their blockers aside). "The best runs are draws and screens."

So welcome to the age of the 300-yard passing game, which used to be as unique as cheers in Philadelphia. Now they're as prolific as Favre health reports. In 2000, QBs threw only 65 300-plus yard games. Last season saw a record 104 such games. So far this season: 92, the second-highest total ever.

The best "runs," in fact are plays designed to get the ball to wideouts and, yes, to the forgotten running backs in open areas just beyond the line of scrimmage -- bubble screens, the plays are called -- where the backs utilize their speed to create YAC (yards after the catch), a term that didn't exist a decade ago. "I don't think Jerry Rice or Chris Carter ever caught a bubble screen," says Green, his voice rising. "It's the new running play."

Of course, there were some singular effects that helped obliterate the running back from your 2010 highlight reel. After Tomlinson, 31, had a solid start with his new team, the Jets, he ultimately showed his age. Johnson, after a record-setting '09, slid to the level of his pitiful Titans. And Peterson, who had one of his most dominant performances of the season (22 carries, 118 yards) in the Vikings' 24-14 upset of the Philadelphia Eagles on Tuesday night, was hurt much of the season -- both physically and by the Favre fiasco.

But neither I, nor Green, see this call being reversed. "We're moving into a passing era," says the coach, "and we're gonna be here for awhile."

Roy S. Johnson, a veteran sports journalist and media consultant, is the editor-in-chief of Men's Fitness. His blog is Ballers, Gamers and Scoundrels.

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