Joe McKnight said Friday that he will leave USC to enter the upcoming NFL draft. "The time is right," McKnight said. "This was my first healthy season and I really don't want to come back and risk injury." McKnight was held out of the Emerald Bowl against Boston College in December amid an ongoing investigation into whether he violated rules by using an SUV that does not belong to him, as well as his relationship with the vehicle's owner, Santa Monica businessman Scott Schenter.