The official list of the Big 12's top 25 players is locked away in a vault in an undisclosed location, but we're revealing the list day by day here on the blog. Here's a refresher on my exact criteria.
No. 20: Tony Jefferson, S, Oklahoma
2010 numbers: Made 65 tackles (44 solo), recovered a fumble, made two sacks and returned one of his two interceptions for a touchdown.
Most recent ranking: Jefferson was unranked in our postseason list of the Big 12's top 25 players.
Making the case for Jefferson: The Sooners star shared Defensive Freshman of the Year honors with the man below him on this list, and I don't see a ton of separation between the two, other than Jefferson's upside, which gives him the nod on this postseason list.
Jefferson holds down Oklahoma's nickel back spot and proved his worth as a true freshman, drawing comparisons to Roy Williams on the way to a big debut year. Because he plays an unnatural position, Jefferson tends to get left off All-Big 12 lists and positional lists, but though there are better safeties and better linebackers in the Big 12, nobody plays the nickel back in the Big 12 better than Jefferson does right now. He's a big hitter and has the speed to seem like he's everywhere, and played his best football at the end of the year.
Both of his sacks came in the season's final two games and he returned an interception for a score in the Fiesta Bowl against UConn. He made 29 tackles in a three-game stretch early in the season against Air Force, Cincinnati and Texas, but the rest of Jefferson's career should be fascinating to watch.
The rest of the list: