It is often very difficult for a rookie to make an impact in the NFL. Obviously there are noted exceptions as players like Robert Griffin and Cam Newton have been dominant since their first NFL game played, but players at skill positions such as running back and wide receiver often take more time to develop and make the transition from the college game to the pros. As a result, the rookie hype that fantasy owners succumb to in say, fantasy baseball, isn't the same as it is in fantasy football. Unless you're talking about an incredibly special player who has been handed the most golden of opportunities, the desire to acquire proven talent over upside and potential is much greater during football drafts.

But that doesn't mean that the rookies are completely ignored and pushed down to the lower rounds of the draft. Over the last few years there have been a number of potential impact players who went much earlier or for more auction dollars than expected. Doug Martin and Trent Richardson were highly-touted college players who were expected to eventually take over the lead position on their respective teams and therefore, had a higher price given the lack of depth at the position. But again, we're talking about high-profile college athletes who have very little competition for their job. Anyone who thought LeGarrette Blount was going to stave off Martin was probably just looking to gain some trade value for a guy about to lose a job battle.

For the most part though, rookies tend to drift towards the middle to lower rounds and as we look at the early ADP numbers below, you'll see not only where the general public sees their value but where they are valued amongst the few expert drafts that have taken place.

With Willis McGahee being released by the Denver Broncos, the expectation is that Montee Ball, the NCAA's touchdown leader out of Wisconsin, will be the team's lead back and garner the majority of touches in the ground game. Knowshon Moreno is coming off a knee injury and Ronnie Hillman is still considered as nothing more than a change-of-pace back. Other backs who will be in camp – Lance Ball, Jeremiah Johnson and C.J. Anderson – don't figure to land prominent roles, but Ball has been around as a back-up and occasional carry-poacher. But Moreno wasn't expected to do much last season either and ended up being one of the top free agent pick-ups during the season and racked up 525 yards on 138 carries and found the endzone four times on the ground. This isn't to say that Montee won't be the dominant back for the year, but with veterans in the backfield, it's understandable why the experts are hedging.

The same goes for Pittsburgh's Le'Veon Bell. With Isaac Redman, Jonathan Dwyer and now La'Rod Stephens-Howling vying for carries, the pundits don't see him as late fourth/early fifth round material. He still may be the lead guy come the start of the season, but from a value standpoint, there are likely bigger impact players available.

Green Bay's second-round pick, Eddie Lacy, seems to be a guy most can agree on as far as draft value. After watching the likes of James Starks, DuJuan Harris and Alex Green come up short on the grand scale last season, the Packers drafted Lacy and then Johnathan Franklin two round later as somewhat of an insurance policy. Lacy and Harris seem to be the favorites to garner the most carries, but the expectation is that Lacy eventually sets himself apart and becomes the lead option.

The running game in St. Louis is one in flux given the departure ofSteven Jackson. There was hope that Isaiah Pead would step into a larger role last year but when Jackson went down, it was Daryl Richardson who began to get the most work. Despite having two young backs on the roster, the Rams opted to takeZac Stacy in the fifth round and many believe he will be the one to separate himself from the pack and eventually land the lead role. But the styles of Stacy and the other two differ and the situation seems more likely to be a shared role unless someone takes a major step forward in camp. Pead and Richardson are considered speed backs while Stacy is the power threat to run between the tackles. And it is for that reason that the experts aren't buying into Stacy as much right now, taking him nearly 70 picks later. Obviously things could change in camp, but for now, this looks like a committee in the making.

With the eighth overall pick in the 2013 draft, the Rams took the first skill-position player off the board in West Virginia wide receiver Tavon Austin. The scouts are high on Austin for a number of reasons, though size – five-foot-eight, 174 pounds – is not one of them. But Austin's speed, his open-field running skills, and his ability to work just as effectively out of the backfield make him a potentially explosive player. So why isn't he going higher than the 100^th pick? Obviously there are some concerns about the crowded backfield and the fact that there isn't a huge array of complementary receivers out there to draw coverage away. Defenses will key in on Austin so not to be burned by his speed and that could hinder some of his fantasy value early on.

Bengals running back Giovani Bernard seems to be the guy to watch as we near closer to the start of the season and will likely begin to see an increase in his overall ADP rank the more the experts write about him. Competing with BenJarvis Green-Ellis shouldn't be too difficult despite a lack of burning speed, as Bernard sees the field extremely well and should prove to be a strong pass-catcher out of the backfield. Bernard impressed during OTAs and will likely see his role expand steadily during camp and in the early weeks of the regular season. He could be the lead back much sooner than people think.

The final three who round out the top 10 aren't quite on the general public's radar right now. Cordarrelle Patterson should play opposite Greg Jennings, but with tight end Kyle Rudolph and Jennings likely to steal the most red zone looks, it limits Patterson's potential. There's also the presence of Jerome Simpson and the fact that so many have been high on Jarius Wright who looked strong in a very limited role last season. Stepfan Taylor sits behind both Rashard Mendenhall and Ryan Williams on the depth chart in Arizona and while DeAndre Hopkins should start, the Texans are a run-dominant team with so much of the passing game headed Andre Johnson's and Owen Daniels' way.

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Howard Bender has been covering fantasy sports for over a decade on a variety of web sites. You can find his personal musings on RotobuzzGuy.com and for questions, thoughts or comments, you can follow him on Twitter at @rotobuzzguy or email him at rotobuzzguy@gmail.com.