tOSU's infamous running back, Maurice "Slo Mo" Clarett, challenged the rule and had temporarily won a judgement, but right before the 2004 draft, it was reversed.
He had only played one year of college ball, since he had that amazing freshman year, and got suspended for his sophomore year (bad behavior, academic dishonesty, basically pissing everyone off).
He didn't play for the 2004 season, and entered the draft 25 lbs overweight, poor cardio, etc., and even though he got drafted in Rd3, he got cut very quickly, due to his bad attitude.
This judgement affected another big time talent, USC's WR Mike Williams. In Williams' case, though, I do feel badly for him, since after the judgement, he tried to go back to school, and in my opinion, had a legitimate case for being able to come back. Williams also had two excellent years at USC as a true freshman and sophomore and was very much ready for the NFL.
At least Williams managed to have a reasonably long career, including a very good season in 2010. I will always have an enmity for him, with his being a USC Trojan, but I do respect his being an unselfish player, even leveling some guy who was about to take a cheap shot at Golden Tate.
On a side note, I do applaud Maurice Clarett for finally getting his head screwed on straight, and making something of his life.