NFL teams targeting quarterbacks in the 2015 draft will need an early pick and an adventurous spirit. There is a steep drop-off after Oregon’s Marcus Mariota and Florida State’s Jameis Winston.

However, there is great depth at some positions.

Among offensive tackles, for example, teams can pick a flavor. The safe option is Brandon Scherff, the tough and technically-sound pupil of Kirk Ferentz at Iowa. Other scouts might be more willing to gamble on the athletic upside of Texas A&M’s Cedric Ogbuehi or Pittsburgh’s T.J. Clemmings. Some clubs prioritize girth, making LSU’s La’el Collins, Stanford’s Andrus Peat or Miami’s Ereck Flowers first-round candidates.

Much will change before the first pick of the 2015 NFL Draft is announced on April 30. As it stands, these are my top 32 NFL prospects in college football.

1. Leonard Williams, DT, 6-4, 290, 4.88, Jr, Southern Cal – Through 10 games, Williams is the best player I’ve seen on the field this season. Strong, athletic and passionate, the Trojans’ star is earning comparisons to everyone from Houston Texans’ defensive end J.J. Watt to Tampa Bay Buccaneers defensive tackle Gerald McCoy for his ability to dominate the line of scrimmage while alternating between defensive tackle and defensive end. He’s too quick for guards and too strong for tackles, wreaking havoc along the line of scrimmage against the run and pass.

2. Randy Gregory, DE, 6-5, 242, Jr, 4.76, Nebraska – Despite Melvin Gordon running for an FBS-record 408 yards against Nebraska, Gregory was impressive against the Badgers. From a two- or three-point stance, he’s a natural pass rusher with an explosive get-off, flexibility, long arms and active hands and the tenacious style of play (including against the run) that will endear him to coaches. That said, there is no guarantee the true junior will make himself eligible for the 2015 draft. Nebraska head coach Bo Pelini repeated that he anticipates all of his defensive linemen returning. Gregory is lanky and needs to bulk up to guarantee remaining at defensive end at the next level. His upside is undeniable and a top five pick seems likely. The fact that an old knee injury was aggravated in the season opener and required a knee scope may ultimately be the scare that pushes Gregory into the draft.

3. Marcus Mariota, QB, 6-4, 215, 4.52, rJr, Oregon – Mariota’s mesmerizing physical traits have long captivated scouts, but he’s also answering questions about his mettle and poise with impressive wins against Michigan State, Stanford and most recently Utah. His performance deserves kudos as Mariota played well under the spotlight and against NFL schemes in these victories. He is not the “Can’t Miss” prospect that some imply. He is potentially a special weapon because of his speed in an era of dual-threat quarterbacks. But he’s a good, not great, passer. Further, Oregon’s speed and scheme complicate Mariota’s projection to the NFL as he won’t see the wide-open passing lanes at the next level.

4. Jameis Winston, QB, 6-4, 235, 4.83, rSo, Florida State – Winston clearly requires thorough investigation before any NFL team is going to be willing to draft him as the face of their franchise. On the field, however, Winston’s talent is undeniable. Winston possesses ideal size, arm talent and rare composure for such a young player, earning his victories this season with remarkable comebacks. He isn’t Mariota’s match in terms of straight-line speed, but can extend the play with his feet and keeps his eyes downfield, showing good anticipation. Given his big-game moxie and experience in a pro-style offense, Winston is an easier NFL projection than Mariota – if, again, he can convince teams of his reliability off the field.

5. Brandon Scherff, OT, 6-5, 315, 4.93, rSr, Iowa — Scherff may just prove the best in the long line of blockers tutored by Hawkeyes coach Kirk Ferentz, which is quite an accomplishment considering that 13 Iowa offensive linemen have been drafted since he took over in 1999. Scherff won big points with scouts for his toughness, battling back from a torn meniscus and corrective surgery on Sept. 8 to start against rival Iowa State five days later. Scherff doesn’t possess special traits like long arms or the flashy athleticism scouts look for and likely won’t be drafted as high as I grade him. He’s powerful, tough and tenacious, however, and I see him as one of the “safer” prospects in the country.

6. Landon Collins, SS, 6-0, 215, 4.53, Jr, Alabama – Instinctive, athletic and an explosive hitter, Collins looks the part of a top 10 pick. His downhill-playing style might be best suited to strong safety as he has been fooled deep on occasion this year due to his aggression. Further, scouts are certainly aware of the fact that few of the highly drafted few defensive backs out of Alabama have performed as brilliantly in the NFL as they did for Nick Saban.

7. Vic Beasley, OLB, 6-2, 235, 4.58, rSr, Clemson — With pressure on the quarterback priority No. 1 on defense, teams are more willing than ever to trade size for speed at the position. Like recent “undersized” first-round rushers Von Miller, Bruce Irvin, Barkevious Mingo and Dee Ford, Beasley boasts a lightning-quick first-step and the agility to stalk mobile quarterbacks.

8. Shane Ray, DE, 6-3, 245, 4.54, Jr, Missouri – Ray had to bide his time backing up Michael Sam and Kony Ealy but Ray has been dominant as a junior, leading the SEC with 12 sacks and 16 tackles for loss. Voted the conference’s Defensive Lineman of the Week three times, Ray is proving that his phenomenal athleticism — he’s been credited with a 4.4-second 40-yard dash and 40-plus vertical jump — translate well to the gridiron. Ray may wind up a top 10 pick, as the perception in the scouting community is that he is just scratching the surface of his potential.

9. Shawn Oakman, DE, 6-8, 275, 4.92, rJr, Baylor – Oakman certainly looks the part of a top-10 pick, boasting an incredible combination of size, burst and power. He remains very much a work in progress, disappearing for stretches in showdowns against TCU and Oklahoma, among other contests. He has shown playmaking ability throughout his career, recording an astounding 12.5 tackles for loss last season despite not starting in his first season after transferring from Penn State. Using a top 10 pick on Oakman is a gamble, but it is a gamble that could result in winning the lottery.

10. Dorial Green-Beckham, WR, 6-5, 225, 4.49, rJr, Oklahoma — The character concerns which prompted Green-Beckham’s transfer from Missouri will certainly require investigating, but there is no denying his blend of size, acceleration and ball-skills. The skill-set is so rare, in fact, that DGB is likely to earn first-round consideration in 2015 even with the NCAA ruling the junior ineligible to play this year.

11. Amari Cooper, WR, 6-1, 205, 4.56, Jr, Alabama — Cooper has great agility and first-step acceleration to generate big plays — something that new ‘Bama offensive coordinator Lane Kiffin has wasted no time in capitalizing on. He may very well prove Alabama’s first winner of the Biletnikoff Award but his lack of elite size and occasional dropped pass keeps him out of the elite category.

12. Dante Fowler Jr., DE, 6-3, 266, 4.84, Jr, Florida — A talented pass rusher with experience at outside linebacker and all over the defensive line, Fowler is an intriguing athlete with range, strength and flexibility. He isn’t as explosive off the snap or productive as some of the other pass rushers on this list but Fowler’s awareness and physicality make him better suited to handling the run. Through social media, Fowler insinuated that he may be heading to the NFL a year early, following news of the firing of Florida’s coaching staff.

13. Cedric Ogbuehi, OT, 6-5, 300, 4.98, rSr, Texas A&M — Former Aggies Luke Joeckel (2013) and Jake Matthews (2014) were the second and sixth overall picks in successive drafts, and Ogbuehi has more raw talent than either player. He’s remarkably light on his feet for a man of his size and possesses the balance and long arms to catch up to pass-rushers even if beaten off the snap. Ogbuehi struggled with the transition from right to left tackle this year, however, and has since been moved back. That’s certainly a red flag but Ogbuehi’s upside is undeniable.

14. Trae Waynes, CB, 6-1, 183, 4.53, rJr, Michigan State — While former teammate Darqueze Dennard won the Thorpe Award last year as the nation’s top defensive back, some scouts questioned if Waynes wasn’t, in fact, the better prospect. Evidence to support this bold theory was offered against Nebraska when the lanky and athletic defender intercepted two passes, including one in the final seconds to seal the victory for the Spartans.

15. Lael Collins, OT, 6-5, 315, 5.12, Sr, LSU — Collins doesn’t get the national attention of other tackles in this class, but the big man is surprisingly agile in pass protection and is a mauler in the running game. Collins isn’t an elite athlete and therefore will likely wind up inside at guard or right tackle in the NFL rather than at his customary left tackle position but he has the square build and physical nature to handle the move.

16. Alvin “Bud” Dupree, DE, 6-4, 267, 4.63, rSr, Kentucky – The Wildcats may not have the history of churning out high-end defenders of some other SEC teams, but that won’t stop Dupree from earning a first round selection. Dupree’s length, agility and closing speed stand out on tape, as does his comfort playing out of the two or three point stance. Better yet, his traits translate into production against quality competition, as Dupree is the SEC’s active sack leader.

17. Danny Shelton, DT, 6-2, 323, 5.17, Sr, Washington – Broad-shouldered, powerful and surprisingly passionate in pursuit, Shelton is a classic two-gap run defender with the gaudy statistics to catch the attention of scouts. He has flashed first-round talent throughout his career but has played at a different level as a senior, boosting his stock considerably.

18. Shaq Thompson, OLB, 6-2, 231, 4.56, Jr, Washington – Boasting terrific athleticism, instincts and awareness, Thompson has proven a standout wherever he’s played for the Huskies, including most recently at running back. While perhaps not as stout as preferred, Thompson’s fluidity, reliable open-field tackling and big play moxie could earn him a hybrid linebacker/safety role.

19. Kevin White, WR, 6-3, 209, 4.49, Sr, West Virginia — No player has improved his draft stock more in 2014 than White. It isn’t just his production (91 catches for 1,207 yards and eight touchdowns) that is impressing scouts. White’s size, strength and ability to come down with contested grabs is something that every team in the NFL is looking for at the receiver position.

20. Melvin Gordon, RB, 6-1, 207, 4.52, rJr, Wisconsin – Long before Gordon broke LaDainian Tomlinson’s all-time single-game record for rushing yards with 408 (in three quarters) against Nebraska, scouts were gushing about his talent. Gordon boasts elite acceleration and great lateral agility to make defenders miss. Lost a bit in the record-breaking storyline is the fact that Gordon fumbled twice against Nebraska and he needs to demonstrate more reliable hands as a receiver. With Georgia’s Todd Gurley suffering an ACL tear — and tumbling out of my Big Board rankings — there is no question that Gordon is the top back in the country.

21. DeVante Parker, WR, 6-3, 209, 4.45, Sr, Louisville – A broken left foot sidelined Parker for the first seven games of the 2014 season but he’s returned with a vengeance since and was dynamic against Florida State, recording eight catches for 214 yards. Parker didn’t just beat Florida State with his size and ability to high-point passes. He also showed impressive fluidity and acceleration for a receiver of his size.

22. P.J. Williams, CB, 6-0, 190, 4.48, Jr, Florida State – Williams has gone up against some of the more talented receivers in college football and succeeded, demonstrating the fluidity, balance and acceleration scouts expect out of a first round cornerback. I’d like to see him wrap more securely on tackle attempts but the traits are there.

23. T.J. Clemmings, OT, 6-5, 305, 5.05, rSr, Pittsburgh – The Panthers boast two of the more exciting young players in college football in James Conner and Tyler Boyd but Clemmings is a potential first round talent in his own right. He’s made steady progress at right tackle since making the jump from defensive end two years ago and boasts an exciting combination of length, agility and tenacity.

24. Devin Funchess, WR/TE, 6-5, 230, 4.73, Jr, Michigan — The sky may be falling in Ann Arbor but Funchess remains a relative ray of sunshine. He has been better at receiver this season than he was the past two years at tight end, demonstrating the combination of size, body control and sticky hands to project very well to the next level. Like the only tight end to earn a first-round pick last year (Detroit’s Eric Ebron), however, Funchess drops more easy passes than he should.

25. Eddie Goldman, DT, 6-3, 314, 5.28, Jr, Florida State — Teams are willing to gamble on difference-makers along the defensive line almost as much as they are quarterbacks, and no defensive tackle has captured the imagination of scouts more than Goldman this season. Powerful, athletic and versatile after starting last as a sophomore at defensive end, Goldman is flying up draft boards.

26. Jaelen Strong, WR, 6-4, 212, 4.55, rJr, Arizona State – Given Arizona State’s up-tempo offense, it isn’t surprising that Strong is productive. The aptly-named wideout is tough to handle because he possesses great size, physicality and hand-eye coordination to make contested grabs look easy and is surprisingly fluid as a route-runner.

27. Andrus Peat, OT, 6-6, 312, 5.28, Jr, Stanford — Peat signed with Stanford as a five-star recruit and possesses the combination of size and athleticism scouts drool over. However, he has experienced notable lapses this season, from getting blown up by Notre Dame and struggling mightily last week against Utah’s Nate Orchard. Peat’s upside warrants early consideration but unless he develops more nastiness to his play, there is doubt that he will fulfill his potential.

28. Marcus Peters, CB, 6-0, 198, 4.52, Jr, Washington – On the field, Peters is the top cornerback in the class. His aggression, length and ball skills (11 career interceptions) are clearly first-round caliber. However, I have some reservations about his straight-line speed and the greater concern is his character. Peters was dismissed from the team by new Washington head coach Chris Peterson Nov. 6 and he was suspended by the previous staff for the first quarter of the 2012 Kraft Fight Hunger Bowl, as well. Pre-draft interviews will be critical for Peters.

29. Benardrick McKinney, OLB, 6-4, 245, 4.58, rJr, Mississippi State — Heisman candidate Dak Prescott certainly deserves credit for the Bulldogs’ run to No. 1 overall in the rankings, but he has been helped by a deep and ferocious defense, the most gifted of which is McKinney. Boasting a freakish combination of size and athleticism, McKinney looks the part of a top 20 pick, though some have concerns about where he’ll fit best at the next level.

30. Ereck Flowers, OT, 6-5, 322, 5.26, Jr, Miami – Flowers returns to the Big Board after a very impressive performance against Mario Edwards, Jr and Florida State. He dropped off the list after undergoing knee surgery in late October but certainly looked no worse for wear against the defending champs. Flowers is light on his feet and balanced in pass protection. He is aggressive and active as a run blocker, including looking for defenders in pursuit. If Flowers checks out medically, he’s a likely first-round pick.

31. Shilique Calhoun, DE, 6-4, 257, 4.72, rJr, Michigan State – Through the first 10 games of the season and Calhoun has already nearly eclipsed last year’s production. That’s quite the statement considering that he earned the Big Ten Defensive Player of the Year last season with 37 tackles, 14 tackles for loss and 7.5 sacks. Calhoun (who currently has 33 tackles, 11 TFL, 6.5 sacks in 2014) is a well-built defender with burst and flexibility. One concern: scouts would like to see more functional strength.

32. Danielle Hunter, DE, 6-6, 240, 4.68, Jr, LSU – Hunter is a lankier athlete than Calhoun, but he is surprisingly strong at the point of attack and uses his length and lateral agility very well to harass quarterbacks — rushing after them or batting down passes at the line of scrimmage. Hunter knocked down three passes, for example, against Alabama. Like many of the pass rushers on this list, Hunter is a work in progress but his exciting skill-set and the value of his position in today’s NFL could push him into the first round if he were to make himself eligible.

Best of the rest:

Arik Armstead, DT, 6-7, 296, 4.96, Jr, Oregon

Ifo Ekpre-Olomu, CB, 5-10, 185, 4.46, Sr, Oregon

AJ Cann, OG, 6-3, 318, 5.18, Sr, South Carolina

Ty Sambrailo, OT, 6-5, 315, 5.27, rSr, Colorado State

Michael Bennett, DT, 6-2, 288, 4.96, Sr, Ohio State

Ameer Abdullah, RB, 5-09, 195, 4.48, Sr, Nebraska

Lorenzo Mauldin, DE/OLB, 6-4, 243, 4.73, Sr, Louisville

Brett Hundley, QB, 6-3, 227, 4.64, rJr, UCLA

Markus Golden, DE, 6-3, 260, 4.72, Missouri

Cody Prewitt, FS, 6-2, 212, 4.59, Sr, Mississippi

Rob Rang (@RobRang) is a Senior Analyst for NFLDraftScout.com, owned and published by The Sports Xchange in cooperation with CBS Sports.