In a verdict that could affect countless claims by athletes who sue sports organizations for head injuries, a Los Angeles jury on Tuesday rejected a lawsuit seeking $55 million by the widow of a former USC football player who said the NCAA failed to protect him from repeated head trauma that led to his death.

Matthew Gee, a linebacker on the 1990 Rose Bowl-winning squad, endured an estimated 6,000 hits as a college athlete, lawyers for his widow said. They alleged those impacts caused permanent brain damage, and led to cocaine and alcohol abuse that eventually killed him at age 49.