What Adrian Peterson Must Do to Cement Legacy as Best Running Back in History

Adrian Peterson eclipsed the 10,000-yard mark for rushing on Sunday with his best performance of the season against the Chicago Bears.

With 35 carries for 211 yards, Peterson now sits at No. 27 on the list of all-time rushers with 10,057 yards. He became the third fastest player to hit the milestone in league history.

This past offseason, we evaluated how Peterson compared to the top 10 rushers of all time, coming off of a near record single-season rushing effort with 2,097 yards.

At the time, Peterson was ranked No. 33 in career rushing yards with 8,849 yards. It seemed inevitable that the reigning MVP would break 10,000 yards, as I projected throughout this season:

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Heading into the 2013 season, it seems almost a certainty that Peterson will break 10,000 yards. If he maintains a similar yards-per-game pace, he will do so in Week 13 at home against the Chicago Bears.

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Right on cue, Peterson continued his almost inhuman level of consistency, helping to carry the Minnesota Vikings on his back to a 23-20 overtime win. He now leads the NFL in total rushing yards (1,208) and yards per game (100.7). 

Many would argue that it's only a matter of time until Peterson enters the conversation as one of the best running backs to ever play. Some would argue he's already in that conversation.

As Peterson turns 29 in March of next season, one question still remains—what would the former Oklahoma Sooner need to do to cement his legacy as the greatest ever?

With so many different ways to measure a running back's impact in NFL history, there has yet to be a clear answer when debating who is the best of all time.

Emmitt Smith leads all running backs with 18,355 yards, but he is often downplayed for doing so in more games than any other rusher, with the record viewed as a matter of longevity rather than an indication of the best pound-for-pound back.

As a result, Walter Payton and Barry Sanders quickly enter the conversation, both totaling more yards in fewer games. Jim Brown shoots to No. 1 in terms of yards per game with 104.3.

Here's a breakdown of the top five career rushing yards leaders in the NFL, with Peterson steadily climbing the charts.

Rank	Player	Yards	Games	Yds/Game	Yds/Carry	SB Wins
1	Emmitt Smith	18,355	226	81.2	4.2	3
2	Walter Payton	16,726	190	88.0	4.4	1
3	Barry Sanders	15,269	153	99.8	5.0	0
4	Curtis Martin	14,101	168	83.9	4.0	0
5	L. Tomlinson	13,684	170	80.5	4.3	0
27	Adrian Peterson	10,057	94	99.6	5.0	0

It's interesting to note that unlike quarterbacks, Super Bowl wins tend to be valued to a lesser degree when evaluating running backs.

That's not to say that the three championship rings for Smith are a throwaway, but they're often credited to the dynasty of the Dallas Cowboys in the 1990s.

And given the ineptitude of the Vikings at quarterback in the foreseeable future, it would be hard to penalize Peterson if Minnesota never makes it to the big dance.

Therefore, we're left scrutinizing every statistical angle, as well as that notion of passing the eye test. The latter often sticks in people's minds when differentiating the class of rushers.

Sanders generally stands as the gold standard for elusive runs. He had the ability to change directions laterally in such a way that you wondered if someone was controlling him with a joystick.

Payton had a similar running style to Peterson, one that was bruising to defenders and rarely avoided contact. Both exploded in the open field with breakaway speed that complemented brute force.

However, Payton was a far superior receiver and blocker than Peterson. If the conversation turns to best all-around running back as opposed to rusher, Payton has little competition.

In order for Peterson to continue to climb the rankings of career rushers, he'll need a solid run of healthy seasons into his mid-30s. Smith was 36 when he finally announced his retirement as the leading rusher of all time.

With four games remaining for the Vikings, it's fair to estimate that Peterson will be pushing 1,600 yards on the year and a career mark of 10,500 at season's end.

If Minnesota's star back can continue a pace of 1,500 yards each season, he would need to strap on the shoulder pads into the early part of 2019 to supplant Smith of his cherished record.

That's ultimately the threshold Peterson must achieve in order to remove any doubt in this conversation—stay healthy and remain consistent. He's already in nearly every major category of efficiency.

Category	Rank	Stat
Rushing yards in single game	1st	296
Rushing yards in single season	2nd	2,097
Rushing yards per attempt (min. 2,000 attempts)	2nd	5.0
Rushing yards per game (min. 100 games)	3rd	99.6

Given Peterson's work ethic and attitude, it's hard to imagine anyone ever ripping the ball from his hands, metaphorically speaking. If his body holds up over the years, No. 28 will likely keep trotting out on the field each season with his trademark smile.

And even through the milestones and accolades, Peterson has found a way to stay humble. When asked about reaching 10,000 yards, this was his response, via Vikings.com:

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It really means a lot. A lot of guys over the years have contributed to it. I was saying earlier, Matt Birk, Steve Hutchinson, Bryant McKinnie, the guys from this year, Sully (John Sullivan), my fullback through the years. Just to be in that elite group, it’s truly a blessing. God has really blessed me to be surrounded by some great guys to help me get to that goal. I sit here and I’m just humbled.

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Peterson may not be considered the best running back in history as of present day, but give him time. He continues to build his resume across every significant category.

The goal for the Vikings will be to build talent around their star asset, avoiding the environment that festered for Sanders in Detroit. If the Lion's running back had played a few more seasons, Peterson might be chasing a different player at the top for career rushing yards.

In the end, the opportunity exists for Peterson to become the best running back in NFL history. But it's still up for debate who that actually is.

All statistics courtesy of Pro-Football-Reference.com, unless otherwise noted.

Matthew Stensrud is a Featured Columnist for Bleacher Report. You can follow him on Twitter and Google+.

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