Although he entered USC as a highly regarded quarterback prospect, Booty spent his first three years at USC as the back-up to eventual
Heisman Trophy winner Matt Leinart, who had replaced former Heisman winner Carson Palmer. When he arrived at USC, the competition for the starting quarterback in the 2003 season had not seen any particular player separating themselves from the pack, so when Matt Leinart was eventually chosen as the starter there was some question as to whether he would merely hold the starting position until Booty could learn the offense.
Booty had back surgery to repair a bulging disc in his spine at the end of March 2006, but fully recovered and earned the starting spot for the 2006 season.
Booty entered the 2006 season as a redshirt junior.
At the beginning of the 2006 season, Booty was one of 15 players on the official watch list for the
Maxwell Football Club for the best player in college football, although the list states that it "may change without notice based on performance ... during the 2006 season and is not designed to represent an all-inclusive listing of eligible candidates for the collegiate football awards presented by the Maxwell Football Club."
In the 2006 season, Booty was ranked the 10th best quarterback in college football and the #1 quarterback in the PAC-10 by Rivals.com.
He started all of the games for the USC Trojans at quarterback in 2006 and was named to the rivals.com and Pacific 10 conference coaches 2006 All Pac-10 team First Team .
On September 18, 2006, USC's sports information director, Tim Tessalone, sent a formal letter to ESPN and a copy to the Pacific Ten Conference complaining that Brent Musburger revealed privileged information in his broadcast of the September 16, 2006 NCAA football game in which the USC Trojans hosted the Nebraska Cornhuskers. Musburger disclosed that he learned from a pre-game conversation with Booty a signal Booty uses to pass to receivers. USC claims this information was for private background purposes only.
Booty led the Trojans to a victory over Michigan in the 2007
Rose Bowl, throwing for 391 yards and four touchdowns
Booty chose to return for the 2007 season, forgoing the NFL Draft. Rivals.com named him one of the top-10 quarterbacks going into the 2007 season,
Sports Illustrated as one of the "Top 20 Players Heading Into 2007" , and he was considered a front-runner for the 2007 Heisman Trophy.
Booty was a 2007 preseason All-American for Athlon,
The Sporting News, and Blue Ribbon and was on the 2007 Maxwell Award and Manning Award watch list. In the summer before the season, he worked out with Indianapolis Colts quarterback Peyton Manning.
On October 6, Booty suffered a broken finger in his throwing hand during a 24-23 loss to Stanford. He sat out the following three games before returning as the starting quarterback against Oregon State on November 3.
On January 1st, 2008, Booty led the Trojans to a victory over the University of Illinois Fighting Illini 49-17 in the Rose Bowl. He was awarded offensive MVP of the game. (Co-MVP with defensive MVP, Rey Maualuga)
USC Trojans Profiles
Joe McKnight: RB
Joe McKnight is a potential difference maker regardless of which position he plays, and he has great football speed despite what his actual 40 time may indicate. He is a jack of all trades and reminds us a lot of a young Eric Metcalf
Mark Sanchez: QB
Mark Sanchez was a highly recruited player and arrived at the University of Southern California in 2005. Mark Sanchez did not play during his freshman year and redshirted.
Chauncey Washington: RB
Another Reggie Bush in the making Chauncey Washington was often nicknamed "The General", perhaps because in the USC's armed forces on the football field he is next in line to the "President" that is Reggie. To his friends, Chauncey Washington is simply "C-Dub".
Aaron Corp: QB
Aaron Corp is a versatile quarterback that can pull the ball down and take off if he has to. He a tough player and knows the game. "I’m good at making my leads and getting the ball where it needs to be. I think I’m a very mobile QB".
Mitch Mustain: QB
Mitch Mustain was one of the most sought-after high school recruits by college football programs during the 2005-2006 school year.