The NCAA rejected USC's appeal Thursday to reduce sanctions imposed on the school's football program.
The ruling means the penalties handed down against the school, including the second year of its two-year postseason ban, will stand. The Trojans served their first postseason ban last season.
"I can assure our student-athletes, coaches and fans that we made every possible argument -- forcefully and vigorously -- for modifying unjust penalties,'' said USC Athletic Director Pat Haden.
USC will be ineligible for the Pac-12 title game -- the conference's first -- and a bowl game.
USC also will lose 30 scholarships over the next three years. The team will have 15 available scholarships per season -- 10 below the normal yearly limit -- until 2015.
The penalties resulted from a four-year NCAA investigation into illegal benefits for Heisman Trophy-winning tailback Reggie Bush.
USC quarterback Matt Barkley tweeted, "Our team will embrace the challenge as one and be stronger for it. Times of adversity are special opportunities to Fight On!''