With spring practice already underway on some campuses and set to begin soon on many others, SI.com identifies 10 high-profile early enrollees who could make an impact this spring -- and this fall. (Listed alphabetically by last name.)
Arik Armstead, DE, Oregon: Armstead had quite the wild recruiting ride. The five-star defensive end -- who is actually rated higher as an offensive tackle, but will exclusively play defense in college -- committed to USC in June 2010, de-committed from the Trojans in the fall of 2011 and looked like he was headed to Cal until assistant Tosh Lupoi moved to Washington in January. That's when Ducks coach Chip Kelly moved in, impressing Armstead enough to get him to sign and enroll early at Oregon. Rivals' No. 61 player should make an impact both on the field and on the court in Eugene: The 6-foot-8, 280 pound Armstead will also play basketball for the Ducks.
Travis Blanks, S, Clemson: Rivals' No. 4 safety and No. 60 overall player, Blanks should do wonders for Clemson's secondary, which was torched for 401 yards and six touchdowns in a blowout Orange Bowl loss to West Virginia. Look for Blanks to make plenty of big plays in Death Valley. He was a top wide receiver in high school and has good ball skills to go along with his big hitting ability.
Joe Bolden, LB, Michigan: Bolden, Rivals' No. 111 overall player and No. 7 linebacker, is a sideline-to-sideline OLB who should see time for the Wolverines this year. It wouldn't hurt for him to add a little bit of weight -- he's just 225 pounds -- but being an early enrollee should help with that. If he can pack on a few pounds while maintaining his quickness, Bolden should be a decent contributor to coordinator Greg Mattison's resurgent defense.
Connor Brewer, QB, Texas: Brewer isn't rated as highly as the other quarterbacks on this list -- Rivals has him as the 10th ranked pro-style passer and doesn't rank him overall -- but he'll still have a chance to see time for the Longhorns this fall. Returning quarterbacks Case McCoy and David Ash were less than stellar in 2011, combining to throw 11 touchdowns and 12 interceptions for a measly 2,113 yards. Brewer, who led Chapparal (Scottsdale, Ariz.) High to three straight state titles, is currently competing with the pair in spring practice.
Bri'onte Dunn, RB, Ohio State: Dunn isn't particularly highly rated by recruiting services -- he's ranked 148th overall by Rivals -- but he could make a big impact in Columbus this fall. The 6-2, 215 pound running back will spend the spring with the Buckeyes after enrolling in January. With last year's starter Dan Herron gone to graduation, Dunn could end up being the featured back as a freshman.
DJ Humphries, OT, Florida: Rivals' top offensive line recruit in the Class of 2012 could start right off the bat for Will Muschamp's Gators. Humphries' speed and size at the tackle position should help Florida correct the offensive line woes it experienced last year, when the Gators finished eighth in the SEC in rushing and struggled to protect quarterback John Brantley.
Gunner Kiel, QB, Notre Dame: Les Miles infamously ragged on the former LSU and Indiana commit on Signing Day, saying Kiel didn't "necessarily have the chest or ability to lead a program" after the Indiana native ditched the Tigers for Notre Dame. Kiel, ranked the nation's No. 20 overall player by Rivals, will have a shot to prove Miles wrong starting this spring, when he'll compete with incumbent Tommy Rees, redshirt freshman Everett Golson and junior Andrew Hendrix for the Fighting Irish's starting job. Kiel should enter South Bend feeling fairly comfortable: He ran a watered-down version of Notre Dame coach Brian Kelly's spread offense in high school.
Zach Kline, QB, Cal: Cal's class suffered major losses after recruiting ace and former defensive line coach Lupoi moved to Washington in January, but the Bears held onto Kline, a highly touted pro-style passer who has been attending camps at Berkeley since he was in the eighth grade. Rivals' No. 44 overall recruit and an East Bay native, Kline is already on campus and will compete for the starting job with incumbent Zach Maynard when camp opens in March.
Mario Pender, RB, Florida State: Pender was an absolute star in his senior year at Island Coast High in Cape Coral, Fla., rushing for 1,543 yards and 17 touchdowns on just 130 carries, good for an absurd 11.9 yards per attempt. Rivals ranks the speedy back 38th overall, and he should help restore FSU's running game, which struggled at times last season. Pender will have to stay out of trouble in order to make an impact, though; he was arrested in November after a domestic incident with his now ex-girlfriend and will be watched closely by the 'Noles coaching staff.
TJ Yeldon, RB, Alabama: Rivals' No. 12 overall player sent shockwaves throughout the Southeast when he switched his commitment from Auburn to Alabama in December. He probably won't be the Tide's starter in the fall -- that honor will likely go to Eddie Lacy, who backed up Trent Richardson last season -- but Alabama's 2011 Mr. Football will no doubt see plenty of time in Nick Saban's standard backfield by committee.