Todd Marinovich, the former Los Angeles Raiders quarterback whose career ended in a mire of drug abuse, is facing a possible prison term after a weekend arrest in Orange County. Marinovich, 38, remained jailed Wednesday on no-bail warrants for probation violation pending a Sept. 6 pretrial hearing. Police said he was skateboarding in a prohibited area near the Newport Pier boardwalk shortly before 1:30 a.m. Sunday and ran away when officers tried to stop him. He was found hiding in a carport about six blocks away.