Ranking top 25 underclassmen

Johnny Manziel, Jadeveon Clowney and Marqise Lee ranked among the nation's best players in 2012. Icon SMI

The 2012 college football season has been a great one for underclassmen.

This season saw the first freshman Heisman Trophy winner in the award's history (Texas A&M's Johnny Manziel), key freshman and true sophomore contributors to both BCS National Championship Game participants (including Everett Golson and Stephon Tuitt for Notre Dame, and T.J. Yeldon and Amari Cooper for Alabama), and several young breakout performers around the country, including quarterbacks at some highly ranked programs.

Which of these underclassmen (true sophomores, redshirt freshmen and true freshmen), none of whom are yet eligible to declare for the NFL draft, performed the best in 2012?

We evaluated these players on tape and ranked our top 25, based solely on film study from the 2012 season. These rankings reflect their skills and value as college football players. This is not an NFL projection.

The list produced some interesting results, with offensive players, particularly running backs and wide receivers, dominating the rankings. The SEC, unsurprisingly, was the conference that produced the most players on this list (the Pac-12 earned second-place honors), but each of the BCS leagues had underclassmen who cracked the top 25.

Here is our ranking of the top 25 underclassmen for the 2012 season.

1. Jadeveon Clowney, South Carolina Gamecocks

Sophomore defensive end

You simply cannot coach Clowney's combination of size, first-step quickness and natural athleticism. Studying coach-copy tape of Clowney and comparing him to other top defensive linemen gave us a true appreciation for his first-step quickness and hand quickness. There are times when it seems like he gets home in five steps with those long strides.

His production ranked among the nation's best in 2012 (in 11 games, he had 21.5 tackles for loss and 13 sacks), but even those gaudy stats can't fully capture what we saw of him on tape in the Georgia game. He was a one-man wrecking crew against the Bulldogs. He played with a foot injury versus Tennessee and Arkansas, which limited him somewhat, and he sat out versus Wofford. He returned with his explosive first step intact in the season finale against Clemson, and he tore that offense apart with 4.5 sacks.

He has some areas in which he needs to improve. His lower-body strength, to anchor, needs to get better, and his leverage is inconsistent (LSU handled him at times when they isolated him and ran in his direction). He also still relies too heavily on his swim moves. He has long, explosively quick hands that will allow him to master an array of pass-rush moves, and he does an outstanding job of transferring quickness to power as a pass-rusher.

He's a notch below where Julius Peppers was when he was coming out of UNC in terms of athleticism for his frame, but he's in the same ballpark.

2. Marqise Lee, USC Trojans

Sophomore wide receiver

Simply put, Lee was the best wide receiver in the country this season. He displays elite quickness, agility and speed, and he is a big-time weapon both after the catch and in the vertical passing game (112 catches, 1,680 yards, 14 touchdowns).