We talk about “impact rookies” all the time leading up to the NFL Draft. But is wide receiver one of those positions that we can count on?

Think of Brandon Marshall: 101 receptions, 1,120 yards and 10 TDs in 2009. There’s a reason the Broncos want a first-round pick to ship him out of town. But is there a rookie prospect who can produce the same numbers next season?

Of course not, and that’s why players like Marshall carry big value on the trade market — and are worth a top pick.

Dez Bryant, Arrelious Benn, Notre Dame’s Golden Tate or any of the rookie WR prospects in 2010 are not going to catch 100 balls in their first seasons. They will make some plays throughout the year, but they will also show signs of inconsistency and will look lost at times.

Even going back to the 2009 class — which had six first-round WRs — only Percy Harvin of the Vikings got to 60 receptions, with the Raiders’ Darrius Heyward-Bey the low man on the season, catching just nine passes. Michael Crabtree, Jeremy Maclin, Hakeem Nicks and Kenny Britt all showed they could be productive, but not as a No. 1 — yet. Lots of talent, but still need more time to develop.

But why is the transition to the NFL a challenge for these rookies, preventing them for putting up numbers like we see from Marshall?

Let’s have a look…

Press coverage

This term will be thrown around all draft weekend, but what does it mean for rookies? These prospects don’t see a lot of corners in college using the proper technique or even lining up in a press position the majority of the time. NFL DBs are the complete opposite, and if you can’t get off the jam on Sundays, you don’t get the ball. Lining up across from Darrelle Revis or Champ Bailey is a lot different than playing in the Big 12 or the SEC.

Reading defenses

We tend to forget that defensive schemes in the NFL can be complex and exotic. Receivers have to be able to adjust their routes from their pre-snap reads, and the learning curve on this is often slow for rookies. Run the wrong route and it can lead to a turnover — or the QB looking to other options the rest of the game.

Speed

Everyone has it at the NFL level. There are no weak corners or safeties that offenses can pick on like they do in college. All corners can turn their hips and run, while every safety can play Cover 2 and get to the deep 7 route or over the top of the post route. And unlike in college, if a DB takes a false step, he has the recovery speed and athletic ability to get back to a receiver’s hip before the ball arrives.

Offensive schemes

Playbooks in the NFL are bigger by nature, and the amount of information a rookie WR has to carry into a ballgame is monumental. Audible systems are more complex, and the game plans are bigger than they’re used to. The mental aspect can’t be hidden by pure talent anymore. Knowing the playbook is part of your job as a pro player — and some rookies don’t understand that.

Film study

It’s the next step in the preparation process. Plenty of rookies think they watched a lot of tape in college, but in the NFL you watch tape all day long. Knowing your opponent is the best way to success, and it takes rookies time to understand how to watch tape and how to gain an advantage from studying defenses. Film study is more than just pressing “play,” and until rookie WRs begin to understand what to look for, they’re a long way from producing.

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