Adrian Peterson's a Saint and the fantasy RB is dying

Looks like there will be a second back on the Second Line in New Orleans. Adrian Peterson has agreed to a two-year deal with the Saints and now I'm starting to question why we're bothering at all with more than one running back spot in the average fantasy football lineup.

Having a talented, veteran back like Peterson teaming up with Mark Ingram does wonders for the options available to Sean Payton in the backfield. It also hacks away at the steadily declining depth in the fantasy running back department.

In an era where the 250-carry running back is going the way of Blockbuster Video, Ingram seemed to be on the verge of becoming the closest thing to a workhorse back this side of David Johnson and Ezekiel Elliott. He is coming off the best season of his career, in which he posted his first career 1,000-yard rushing season with a combined 10 touchdowns.

But it feels like we can squash any talk of an encore in 2017. Adrian Peterson might be 32 years old and coming off a pair of serious knee injuries, but he's also the second-leading active career rusher in the National Football League and is still a physical specimen. The only real question is whether the Peterson we saw the past two years is the player who averaged just 1.9 yards per carry last season or the guy who was an unquestioned RB1 for so many years in his career -- or somewhere in between.

What works in AD's favor is that he'll run behind a far superior offensive line. The Vikings front struggled to open holes last season -- as evidenced by their league-worst 3.2 yards per carry average -- whereas the Saints were rated as the top run-blocking offensive line by Football Outsiders.

There's also the issue of the Saints operating a pass-heavy offense. New Orleans ran the second-most pass plays of any team in the league in 2016. That's not likely to change significantly even with Peterson in tow. While AD can catch the ball out of the backfield (he caught a career-high 43 balls in 2009), it's not his strong suit. Ingram, on the other hand, has steadily become a bigger part of the passing game in New Orleans.

The problem is that having Peterson in New Orleans will also drag Ingram down to his (draft) level. Peterson was tracking as an RB2 heading into the summer with Ingram potentially as a fringe RB1. Now, it's hard to envision Ingram as more than an RB2 with Peterson dropping down a tier.

Marcas Grant is a fantasy editor for NFL.com. Follow him on Twitter @MarcasG.