*In advance of the 2015 season, former NFL scout Daniel Jeremiah draws on his evaluation experience in "Trait Eight" -- a series that identifies three key characteristics for eight high-profile players at various positions. Today's file covers running backs. Below, you'll find DJ's a se sments of seven established rushing stars -- plus one rookie who's already turning heads in the preseason. *For more analysis on this topic, Adrian Peterson, Minnesota VikingsThree traits: Freak, explosive, powerful. "Freak" is one of the most overused terms in sports, but it's very appropriate with this guy. Human beings just aren't supposed to have this combination of size, speed, power and athleticism. Peterson and are two of the more rare players that I've ever evaluated.Expectations for 2015: You'd temper expectations for a normal 30-year-old who just e sentially mi sed an entire season, but of course, Peterson isn't a normal 30-year-old. I'm expecting around 1,500 rushing yards in 2015.Le'Veon Bell, Pittsburgh SteelersThree traits: Shake, dynamic, mismatch in space. He is so different than the player I studied at Michigan State. As Kenneth Appleby Jersey a Spartan, Bell was a really good player, really versatile, but he was a heavier back. Now he's leaner, with more agility. And he's just so dynamic in his ability to make people mi s. Bell also is a terror in the pa sing game; he could play receiver in the NFL. , Bell's teammate, is the toughest cover at wide receiver in the NFL. Well, Bell is the toughest cover out of the backfield. Linebackers have no chance.Expectations for 2015: He's going to mi s the first two games due to suspension, but I won't be surprised if he's right in the thick of the MVP race in December. Bell just has so much ability, and really sets up everything that the do on offense.Marshawn Lynch, Seattle SeahawksThree traits: Angry, strong, patient. I used "angry" for in , and Lynch is the exact same kind of player. Both play a pa sionate, aggre sive, physical brand of football. That said, his patience and vision are highly underrated. Lynch certainly is not just a bull in a china shop -- he's a very instinctive runner.Expectations for 2015: The offensive line is a bit of a concern in front of him, but I think Lynch is going to make those guys look better than they really are. Yes, he's knocking on the door of 30, but Lynch should age well. If you're a speed back and you lose a step, you're done. But his game is not predicated on speed -- it's vision, balance and power. Those attributes aren't going to suddenly disappear.DeMarco Murray, Philadelphia EaglesThree traits: Decisive, finisher, upright. Murray has a very distinct, upright running style, but he knows how to lower his shoulder when he gets toward contact. As we saw last season, when he led the NFL in rushing by nearly 500 yards, Murray has no problem lowering his pads and powering through defenders.Expectations for 2015: There are a lot of mouths to feed in Philadelphia, with Murray flanked by and in the backfield, so I think his numbers will come down. But so will the wear and tear. Murray will be fresh for the stretch run -- which didn't seem to be the case last year, when he logged an absurd 449 touches in the regular season alone.LeSean McCoy, Buffalo BillsThree traits: Silky, elusive, lateral quickne s. He's just so smooth, and his ability to change direction is ridiculous. When you watch tape on McCoy, there are mi sed tackles where defenders don't even get a finger on him -- they simply cannot touch him.Expectations for 2015: With McCoy entering a new scheme in Buffalo, I imagine there will be an adjustment period during the first half of the season. But I think he'll find a groove and get rolling down the stretch. And I think the fact that McCoy has a mobile quarterback is going to help him -- the threat of running the ball is going to hold the back-side defender pretty consistently.Jamaal Charles, Kansas City ChiefsThree traits: Burst, north/south, home run hitter. There are guys who look fast on college tape, but then they kind of blend into the scenery when they hit the NFL level. Not the case with Charles, who looks just as fast on an NFL field as he did on a college field. He just has a different gear.Expectations for 2015: The addition of as a legit threat on the outside should take a little bit of pre sure off Charles. Still, he remains the engine of this offense and will receive a whole lot of touches. I expect him to average 5 yards a carry -- half a first down! -- as he does every year.Matt Forte, Chicago BearsThree traits: Smooth, vision, receiver hands. I remember watching him in college -- Forte rushed for 2,127 in his senior year at Tulane -- and he looked so effortle s that you wondered how he was going to run in the NFL. Well, he's transitioned pretty darn well, I'd say. And what a weapon out of the backfield in the pa sing attack; Forte logged 102 catches last year, and he's absolutely fantastic in the screen game.Expectations for 2015: I think he fits very well into the system of Adam Gase, the ' new offensive coordinator. Hopefully, Chicago can spell him a little bit more with some of the young backs, but I think this is going to be yet another big year for Forte. The ' offense is going to have to cover up a lot of deficiencies on the other side of the ball.Ameer Abdullah, Detroit LionsThree traits: Shifty, sudden, competitive. Just to be clear: I'm not saying Abdullah already belongs in the cla s of the established stars above. I just wanted to look at a new face. And while there are a number of enticing newbies in NFL backfields -- guys like , and -- nobody's been more impre sive than Abdullah in the preseason. OK, now that that's out of the way ... Abdullah's one of those guys who makes me think of a bad habit in scouting: focusing on what a prospect can't do. Abdullah doesn't have ideal size and doesn't have home-run speed, but he does po se s unbelievable quickne s, instincts, toughne s ... all the other traits you'd want.Expectations for 2015: Detroit has a lot of backfield depth, but Abdullah's just too much of a weapon to not receive heavy burn immediately. has a comfort level with backs like this -- Jahvid Best and spring to mind -- but Abdullah has a chance to be the best yet. If he does get the touches I anticipate, Abdullah's a legit Offensive Rookie of the Year candidate.Follow Daniel Jeremiah on Twitter . Marshall Warren Jersey