Throughout the preseason, we’ll take a look at the best – and worst – the NFL has to offer, unit by unit. Look for a new set of rankings every few days.

It is true every year that no matter what position a rookie plays for his new NFL team, the young man will have some growing pains. Players and coaches who have played the game or have been around football long enough say that the jump from high school to college is huge, but the jump from college to the pros is colossal. That doesn’t mean that rookies can’t be successful, and a handful of first-year pros every season make that look a little bit easier than most.

In 2005, Tampa Bay running back Carnell “Cadillac” Williams rushed for 1,178 yards and was named the Offensive Rookie of the Year. More importantly, he gave the Buccaneers a rushing attack that had been missing since their Super Bowl win in 2002. Chargers’ linebacker Shawne Merriman won Defensive Rookie of the Year, showing that he could take over games with his athleticism and fearlessness.

Winning NFL Rookie of the Year honors are great, but who is the next Lofa Tatupu, who gave the Seahawks leadership in the middle of their defense and a guy who already commands respect from his teammates?

Here is a list of 10 rookies that have ROY potential or who will make the biggest impact for their teams:

1.Vernon Davis, TE
San Francisco 49ers
Although there have been whispers that some in the 49ers’ organization expected Davis to have picked up the offense quicker than he has to this point, he is still the most physically gifted athlete that came out of the ’06 draft. Will he help the 49ers win the NFC West? Not this season, but he could very easily win Offensive Rookie of the Year with his 4.38 speed and offensive lineman strength. Quarterback Alex Smith will probably rely on Davis to be his go-to-guy in the red zone this year and use Davis’ 6-3, 253-pound frame near the goal line.

2. A.J. Hawk, LB
Green Bay Packers
No other linebacker from the 2006 draft has as much sideline-to-sideline running ability as A.J. Hawk. Hawk is extremely athletic and will soon show the same dynamic playmaking ability in Green Bay as he did for Ohio State in college. He should be great in pursuit and head coach Mike McCarthy will probably use Hawk a lot in blitz packages to take advantage of his athleticism. The Packers defense ranked seventh in the NFL last year, but lacked turnovers and big momentum-swinging plays. Watch for Hawk to fill both of those roles this season and beyond.

3. Mike Bell, RB
Denver Broncos
Denver puts out 1,000-yard rushers in its zone-blocking scheme like Tom Hanks puts out Oscar performances. Six years ago the Broncos drafted an unknown running back named Mike Anderson out of the University of Utah in the sixth round. In his rookie season, Anderson rushed for 1,487-yards and convincingly won the Offensive Rookie of the Year honors. This year, head coach Mike Shanahan seemingly has found another diamond in the rough with undrafted rookie free agent Mike Bell. Bell has already been named the starter and if he holds off Tatum Bell, he too may be up for OROY honors come the end of the season.

4. Ernie Sims, LB
Detroit Lions
Sims is a locomotive who could possibly knock himself out after every tackle because of how hard he hits. The former FSU product will have plenty of chances to make plays in the Lions’ defense this year because the squad might be on the field a ton while the offense tries to pick up Mike Martz’s system. Sims is fast, which is perfect for the weakside linebacker position, and he’ll get plenty of chances to blitz opposing quarterbacks this season. He’ll just need to stay concussion-free – something he wasn’t been able to do while in college.

5. Haloti Ngata, DT
Baltimore Ravens
He doesn’t have the name power of a Mario Williams or A.J. Hawk, but Haloti Ngata will serve as a vital piece in the middle of the Ravens line. Ngata will allow fellow playmakers Terrell Suggs and Trevor Pryce to get to the quarterback more often, as well as keep guards off of middle linebacker Ray Lewis the way Tony Siragusa did for the Ravens during their Super Bowl run in 2000. Ngata may get overlooked this season because of the limited impact defensive tackles make in the stat book, but Lewis and the rest of the Ravens’ stout defense will surely notice his presence.

6. DeAngelo Williams/Joseph Addai/ Lawrence Maroney
Carolina Panthers/Indianapolis Colts/ New England Patriots
One, if not all three, of these players may start for their respective teams this season because of who is in front of them on the depth chart. Williams has the injury-prone DeShaun Foster in front of him while Addai is battling with the unproven Dominic Rhodes and Maroney is behind an aging Corey Dillion. All three of these teams could possibly vie for a Super Bowl this season and will need a heavy run game to complement solid passing systems. The trio should all have an impact this season, but if I’m handicapping their respective situations, I think Addai will be a starter earlier this season than the other two backs. Regardless, all three runners will be the feature back for their respective teams in the near future.

7. Mario Williams, DE
Houston Texans
Williams may never make Houston fans forget about Reggie Bush, but he will have an impact this season for the Texans. Williams’ physical tools are superb enough to register 10 sacks as a rookie, but the trouble is that he doesn’t have a whole lot of support from the rest of Houston’s defense. He fits the mold of Julius Peppers and he’ll give the Texans more playmaking opportunities than they’ve had in the entire history of their franchise. If the Texans can figure out a way to improve his supporting cast, watch out, because Williams will start taking over games the way Peppers does.

8. Reggie Bush, RB
New Orleans Saints
He won’t start because of Deuce McAllister, but the Saints will certainly get Bush on the field. Bush may line up as a single back, as a slot receiver, or in two-back formations with McAllister and New Orleans will take advantage of his elusiveness. Bush may be too small to be a 20-25 carry guy and he may soon find out that life in the NFL is harder than it was at USC, but he will no doubt make plenty of highlight reels this season.

9. D’Brickashaw Ferguson, OT
New York Jets
This guy is just an absolute monster and will give the Jets a solid left tackle for years to come. Ferguson is 6-6, 313 pounds, has great technique and strength, and demonstrates terrific feet while playing the run or pass. It’s just too bad the Jets don’t have that much offensive firepower right now in RB Kevan Barlow and QB Chad Pennington for this kid to get noticed.

10. Kamerion Wimbley, LB
Cleveland Browns
Wimbley would without a doubt be ranked higher if I knew he was going to start sooner this season. He stands behind Willie McGinest and Matt Stewart on the depth chart, but will certainly start sometime this season or in the very near future. Wimbley has loads of talent and his switch from defensive end at Florida State to linebacker in Romeo Crennel’s 3-4 defense will suit him great. He’s more athletic than Stewart, but doesn’t match Stewart’s experience or sure-tackling ability. However, Wimbley should contribute big time in blitz packages this season, and watch for him to be close to five sacks at the end of the season.