23. Andrew Luck (Stanford)
Another guy who passed on the chance to become the #1 overall pick in the NFL Draft as a junior, only to return to school as a senior, quarterback Andrew Luck was hailed by many as the most complete quarterback prospect to enter the NFL Draft since John Elway (who, coincidentally, also went to Stanford University like Luck).
Before Luck had arrived, Stanford had never won more than 10 games in a season; Luck led them to 12 wins in 2010. Stanford’s highest win total in two consecutive years was 18, whereas Luck took them to 23 wins between 2010 and 2011.