"I want people to know that I'm walking away, not running," Carlisle said in a statement on the school's website. "There's not a reason for me to leave except that this is a great opportunity for me to continue my career and take a step in my evolution as a strength coach. Also, this is an opportunity to work with Pete Carroll, which is a heck of an opportunity and one that's very difficult to turn down.
"Lane Kiffin and the USC administration wanted me to stay and I really appreciate that."
Carlisle arrived at USC in 2001, after serving three seasons as the associate head strength and conditioning coach at Tennessee, and was a key member of Carroll's staff that returned the football program back to national prominence.
The 47-year-old was named the 2006 National Collegiate Strength and Conditioning Coach of the Year by the Professional Football Strength and Conditioning Coaches Society.
During his nine seasons at USC, the Trojans appeared in nine bowl games, including a run of seven consecutive BCS bowl appearances.
"I truly believe the transition will be seamless with this new staff," Carlisle said. "Lane Kiffin and his staff will continue setting the bar in college football and maintain the standard of excellence at USC."
With the departure of Carlisle, Jamie Yanchar, who has been at USC since 1990, will serve as the interim strength coach as the new coaching staff looks for Carlisle's replacement.
Chris Carlisle was a key member of the USC program during the Pete Carroll era.
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