USC men's basketball coach Tim Floyd sent a brief one paragraph letter of resignation to athletic director Mike Garrett on Tuesday, officially ending a four-year coaching tenure marked by success on the recruiting trails, but underachieving squads and rumors of impropriety. Floyd had been connected to several high-profile job openings this winter, including an interview that put him at or near the top of the coaching search at Arizona. He also was plagued by reports of recruiting violations involving former star player O.J. Mayo, who played one season in Los Angeles before bolting for the NBA.