The Vikings haven't drafted a running back in four years, but that could change next weekend.

From 2010 to 2013, Toby Gerhart rode shotgun to Adrian Peterson, who is the engine of the Vikings offense. But they let him walk as a free agent in March, leaving a void behind Peterson.

Peterson is 29 and has 2,033 regular-season carries on his odometer, but besides his recent abdominal injuries, he hasn't shown any major signs of slowing down. In 14 games, Peterson ranked fifth in the NFL with 1,266 rushing yards in 2013 and also rumbled for 10 touchdowns.

But Peterson can't carry the ball every single time, which made Gerhart a valuable reserve.

Gerhart averaged 4.7 yards per carry in his Vikings career and had an impressive 7.9 yards per carry -- albeit on just 36 rushing attempts -- before he was sidelined by injury in December.

With Peterson hobbled and Gerhart inactive, the Vikings were forced to rely on Matt Asiata, a little-known 26-year-old with little experience. He rushed for 51 yards and three scores in his first NFL start, but it took him 30 carries to get there. He fared better with 115 yards in Week 17.

Heading into the draft, Peterson is the only proven commodity on the depth chart (sorry, Mr. Asiata, but you're not established quite yet). They also have Joe Banyard and Bradley Randle, neither of which has carried the ball in a regular season game (though Banyard has caught one pass).

The Vikings are expected to address the position at some point in the draft, though they won't use their top pick like they did with Peterson in 2007. The top backs in this draft include Ohio State's Carlos Hyde, Arizona's Ka'Deem Carey and Auburn's Tre Mason, and the Vikings have also gotten under the hood of other running back prospects over the past couple of months.

PROJECTED STARTERS: Peterson, of course, with Jerome Felton bulldozing a path for him.

DON'T FORGET ABOUT: Banyard, signed as a street free agent in 2012, is not the fastest back, but he's a willing inside runner who reads his blocks well. He got lost in the shuffle behind Asiata last season, but he will get an opportunity to prove himself to the new coaching staff.

LEVEL OF NEED: Moderate. Peterson is still the best running back in the game, but Father Time eventually tackles every man, and he does it sooner with running backs than any other position. The Vikings need a reliable backup. Finding Peterson's eventual replacement would be a bonus.

FIVE PROSPECTS TO REMEMBER: Mason, Carey, Florida State running back Devonta Freeman, Towson running back Terrance West and Oregon runner/receiver/returner De'Anthony Thomas.

OUR BEST GUESS: The Vikings will take a running back, perhaps as early as the third round.