By Tony Pauline, Special to SI.com

	Oklahoma linebacker Jonathon Jackson ran an impressive 4.58 40-yard dash. Brian Bahr/Getty Images

"Diamonds in the rough."

It's a common term easily thrown around every April. All NFL teams hope to find at least one in the middle or late rounds of the NFL Draft since those players are inexpensive rookies who contribute in unexpected ways. Here are 10 prospects on the board who potentially fill this role.

1.) Roydell Williams, WR, Tulane
Since his freshman campaign with the Green Wave, Williams has been a dominant force on an offense that likes to throw the ball. Displaying abilities as both a game-controlling and game-breaking receiver, he was the go-to guy opponents were unable to stop. A late addition to January's Senior Bowl in Alabama, Williams ended up as one of the week's best pass-catchers during the all-important practices. And after being snubbed by the Combine, the 190-pound Williams ran an under-4.5 second 40-yard dash during pro-day workouts. He has reliable hands and a preternatural ability to catch touchdown passes; he'd be a perfect fit as a third receiver.

2.) Sean Considine, S, Iowa
Iowa safeties have been a quiet success story in the NFL. Players such as Matt Bowen and Damien Robinson came into the league as middle-round choices and went on to productive careers. Considine could be the best of the bunch. Athletic, intelligent and tough, he combines all the elements needed to be productive right out of the gate. Although he didn't have a spectacular career with the Hawkeyes, he was consistent and made few mistakes. After turning in one of the better Combines no one seems to be talking about, Considine will be a steal late in the draft's first day and could start as a rookie.

3.) Jordan Beck, LB, Cal Poly
Ultra-productive on the small-school level, Beck opened eyes with his postseason performances, yet he rarely gets mentioned among the draft's top linebackers. A consistent defender who averaged 125 tackles each of the past three seasons, Beck's pass-cover skills are on par with the top linebackers on the  board. He played middle backer in college, but he'd make a natural transition to the outside in the NFL and also could be used on the inside on a team using a 3-4 scheme.

4.) Jay Ratliff, DL, Auburn
The best way to characterize Ratliff is "explosive force." As both a defensive tackle and end in college, he showed a solid combination of size, speed and tenacity. It's shocking that he didn't get an invitation to the Combine. His versatility will make him invaluable at the next level and he'll be a bargain in the middle rounds.

5.) Dante Ridgeway, WR, Ball State
Ridgeway put together consecutive seasons of 1,000-plus yards receiving while breaking the MAC single-season mark for receptions with 105. He also had the best pass-catching workout of any receiver at the Combine, and seems headed for a very productive NFL career. At just under 6 feet and weighing 212, he's a prototypical possession receiver who should produce immediately.

6.) Todd Herremans, OT, Saginaw Valley State
Herremans is probably the best offensive lineman you've never heard of. At 6-foot-6, 303 pounds, he's a king-sized blocker with above-average athletic ability. Like most small-school prospects, he'll need time to polish his game; but he has real NFL potential.

7.) Kelvin Hayden, CB, Illinois
A former wide receiver who made the switch to cornerback as a senior, Hayden showed flashes of brilliance during an injury-plagued '04 season. He has the size and speed required to succeed at the next level, so it might be a matter of giving him the time to develop before he becomes a starting corner in the NFL.

8.) Stanford Routt, CB, Houston
A sprinting champion in college, Routt is moving quickly up draft boards. He backed up a terrific Combine workout with good performances during his individual workout. A patient team could see Routt eventually develop into a starting corner.

9.) Jerome Collins, TE, Notre Dame
At face value, a tight end who caught just six passes for 67 yards wouldn't seem to be a prospect. But Collins played linebacker before switching as a senior to the offensive side of the ball, and he's a 267-pounder who ran a 4.75 in the 40. That adds up to a late-round pick who could be a productive NFL player.

10.) Jonathan Jackson, OLB, Oklahoma
With all the great talent Oklahoma has put into the NFL recently, it seems impossible that a current player could fly under the radar. Jackson did because his play leveled off during the last two years; as a sophomore, he was a pass-rushing force who terrorized opposing quarterbacks. But he increased his stock at his pro-day workout by running a 4.58 40. He has starting potential as an outside linebacker in a 3-4 defense.

• TFY's 2005 NFL Draft Preview • TheNFLexperts.com