NFL Draft risers, sliders: Week 12

College football's regular season is coming to a close and the opportunity for NFL hopefuls to impress league scouts is dwindling. This weekend has witnessed a number of lesser known prospects, who usually go unnoticed, step to the forefront and improve their draft stock.

Jonathan Cooper, G -- North Carolina: Cooper received first round grades from scouts prior to the season and has surpassed expectations on the field this year. He was stamped as the premiere zone-blocking lineman in the nation and Cooper has expanded his game in 2012. The athletic guard improved his power at the point of attack and now displays the ability to beat down defenders on the line of scrimmage as well as annihilating opponents blocking in motion. Cooper will be the second guard selected in April 's draft after Alabama's Chance Warmack. He is unlikely to make it out of the draft's initial 15 choices.

Leon McFadden, CB -- San Diego State: McFadden has been steadily rising up draft boards since the start of the season and is another who is exceeding expectations in 2012. He's a feisty cornerback with next-level size and the ball skills to match. McFadden has intercepted three passes this season, broken up 10 throws and has 57 tackles to his credit. He continues to improve on the field and several scouts feel McFadden will be a top-75 pick in next year's draft.

Scott Vallone, DL -- Rutgers: Vallone is perhaps the most unheralded player on the Scarlet Knights' talented defense yet the NFL is aware of his ability. Vallone is smart, tough and a defender who does the little things well. His intensity is infectious as Vallone plays through the whistle and disrupts the opponents game plan. He's not a player who puts up big stats but rather a reliable defender that does not make mental mistakes. Vallone lacks classic size for the next level (6-foot, 3-inches, 280-pounds) yet gets the most from his ability. His game is similar to New York Jets defensive lineman Mike DeVito and Vallone has risen from undrafted free agent to late round pick.

William Campbell, DT -- Michigan: Campbell is another defensive lineman who does the dirty work up front and allows teammates to make plays on the ball. He was credited with two assisted tackles during the Wolverines blowout victory over Iowa, but statistics don't tell the story. The big bodied defender clogged the middle of the line and stopped Iowa's running game. Campbell was not graded by scouts entering the season yet has played his way into the late rounds of the draft.

Kyle Van Noy*, LB -- BYU: Van Noy is one of the centerpieces for a BYU defense which ranks as one of the best in the nation. He's a versatile three-down defender with the ability to line up at several linebacker positions. Van Noy is both tough and instinctive, consistently making positive plays on the field while limiting mental mistakes. Scouts have stamped the junior with a second-day grade.

Gabe Jackson*, G -- Mississippi State: Jackson is a massive lineman who has taken his game to another level this season. He possesses terrific power and easily controls defenders at the point of attack. At the same time Jackson easily moves his 320-pound frame around the field and flashes skill-blocking in motion. He's a third-round prospect with great upside and word is the junior is headed to the draft at the end of the season.

Brian Mulroe, G -- Northwestern: Mulroe gets little notice in the Wildcats non-stop offense yet is an efficient blocker that NFL decision makers have taken a liking to. He offers good size and plays fundamentally sound football. Mulroe displays skill as both a run-blocker and pass-protector. He won't wow scouts with great athletic performances yet many feel this late-round pick will be a productive NFL player.

Shayne Skov, LB -- Stanford: Skov was graded as a potential first-round pick at the start of the 2011 season before a knee injury during the third game ended his season. His return to form was slow this seaso, yet Skov has gotten stronger each week. His performance during the upset victory over Oregon was nothing less than dominant. The ferocious linebacker led the Cardinal with 10 tackles and single-handedly stopped an Oregon scoring opportunity in the first quarter. While the draft world is abuzz about the prospects of middle linebacker Manti Te'o being a top 12 choice, many scouts feel Skov in Round 2 could be better value.

Will Davis, CB -- UtahState: Utah State withstood a furious comeback from Louisiana Tech to win a thriller in overtime, 48-41. Despite the Bulldogs' second- half air attack, Davis was effective and continues to impress NFL scouts. His interception at the end of the first half denied Louisiana Tech a scoring opportunity, which turned out to be the difference in the game. Davis has recorded four interceptions and broke up 16 passes this season to go along with 52 tackles. The junior college transfer has watched his game take off since becoming a full-time starter in 2012. He was graded as a free-agent prospect entering the season, but several scouts recently stamped Davis as a first-round pick.

Reid Fragel, T -- OhioState: Fragel made the successful transition from tight end to right tackle this season and his play has scouts buzzing. He offers NFL size (6-7, 290) and possesses a frame which will grow over time. Fragel displays power in all aspects of his game and plays with surprisingly sound fundamentals. He needs work to complete his game, but Fragel has been graded as a top 100 pick by a number of scouts.

Kyle Long, OL -- Oregon: Long is rarely mentioned outside scouting circles, but the junior college transfer is quickly rising up draft boards. The athletic lineman blocks with terrific fundamentals and shows tremendous skill blocking in motion. He offers potential at both offensive tackle and guard, and like his father Howie Long, figures to be selected somewhere inthe middle of Round 2.

Keenan Davis, WR -- Iowa: Davis entered the season ranked as a potential late-round pick yet has struggled all year. His production has significantly dropped off compared to 2011 and Davis has yet to accumulate 100 receiving yards or more in any single game this year. He's also registered just on touchdown catch this season, a poor number for a big-bodied, possession receiver.

Jawanza Starling, S -- USC: Starling entered the 2012 campaign ranked as a potential first-round pick yet has played more like a last-day selection. The athletic safety has looked indecisive and slow to react. He's usually a half-step late arriving to the action and has struggled defending the run this year.

Russell Shepard, WR -- LSU: Shepard made a last-minute decision to return for his senior season after struggling through an injury plagued 2011 campaign. He's struggled for playing time this season and has totaled just six receptions for 92 yards. The speedy wideout looked like a star in the making after posting 33 receptions as a sophomore. His combined totals the past two years are 20 receptions with 282 receiving yards. Shepard was viewed as a possible mid-round choice but is unlikely to be selected at any point in April's draft.

• Rutgers cornerback Logan Ryan, a Week 3 riser, continues to impress scouts. His second-quarter interception denied Big East foe Cincinnati a scoring opportunity and helped keep the Scarlet Knights undefeated in the conference. The belief is Ryan, recently ranked the 50th best prospect on the SI.com draft board, will leave for the NFL at the end of the season.