When it comes to rushing yards in a season, 2,000 yards is an almost mythical barrier. Only seven running backs in history have surpassed the total, and only two - Adrian Peterson in 2012 and Chris Johnson in 2009 - have done so in the last decade. We aren't exactly in a golden running era in the league - teams spend too much time passing for that - so when a running back puts up big numbers it is particularly impressive.

Bovada offers a prop bet this year on whether we will see a 2,000-yard rusher. Given that the "yes" side is at +600, it is almost impossible to justify a bet (the "no" sits at -1000, so isn't particularly attractive because of the potential payoff despite the likelihood of success). Still, given how exciting it would be to have another entrant in this exclusive club, it doesn't hurt to break down the field to see who could pull it off:

Adrian Peterson, Minnesota Vikings (4/1 favorite to lead league in rushing at Bovada): Peterson entered the club two years ago, and last year he was determined to beat Eric Dickerson's all-time record of 2,105 yards. Unfortunately, little went right. He did not get off to a strong start, and he was on a lousy team. He had his highlights - like 211 yards against the Bears - but was not consistent, and he missed two games late in the season with the death of his son. It was all but a lost year.

So, the question is whether he can get back into form this year. The elephant in the room we can't avoid is that Peterson is now 29 years old and entering his eighth year in the NFL. Running backs generally aren't entering their prime at that age, and there is a lot of wear on these tires - and knees. That's not to say that Peterson can't have a great year again - other backs have at this age or older. It's just that the odds are increasingly stacked against him. He also will be playing outdoors at home this year as the Metrodome is no more, so conditions may not be as ideal for him in some games later in the season.

On the other hand, though, the guy is the most talented back in the league by a wide margin. He is also going to have plenty of opportunities to shine because regardless of what the team does at QB they are not going to be dominant through the air. He is also hungry and focused and is smart enough to know that his window for breaking the record is very small - this might be his last good chance.

If anyone is likely to eclipse 2,000 yards it is Peterson, but given the negatives I just can't justify betting that he will do so.

LeSean McCoy, Philadelphia Eagles (9/2): Can the defending rushing champ up his game this year? He needs to move forward significantly from his 1,607 yards last year to have a shot here. He still has a great offensive line to run behind, and Chip Kelly's up-tempo offense will keep defenses on guard and will provide opportunities for McCoy to shine. Still, I don't like his chances.

He had a league-best 314 rushing attempts last year. With the addition of Darren Sproles he isn't likely to see that number increase significantly, and it could easily go down. He needs all the carries he can possibly get - Peterson had 348 when he broke the 2,000-yard barrier. McCoy also missed a day of practice recently with what he described as minor turf toe that caused incredible pain. He and the team have been quick to minimize the injury, but at toe problem is something that could linger and really derail things.

A guy wanting to eclipse 2,000 yards can't really afford even a single game off. I don't like his chances at all.

Jamaal Charles, Kansas City Chiefs (7/1): Charles is the third and final of what qualifies as the legitimate contenders here. He has been a top-four rusher each of the last two seasons, so he can carry the ball. He has had only 259 and 285 carries in those two seasons, respectively, though, and it is very unlikely on his team with Andy Reid coaching that he is likely to get nearly 100 more carries - which he would need to succeed. He's also potentially fragile - this is the guy who missed the second preseason game this year because he hurt his ankle carrying a box out of his dorm room at the end of training camp.

I like Charles a lot, but he just doesn't have what it takes to eclipse 2,000 yards.

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