Steelers' safety Troy Polamalu left Sunday's game against New Orleans after sustaining an unspecified head injury late in the first quarter. Polamalu, an All-Pro safety last season, was hurt during a Saints touchdown drive that cut Pittsburgh's lead to 14-7. He was examined by doctors on the Steelers' sideline and, while he was not taken to the locker room, remained on the bench for New Orleans' next possession with Tyrone Carter taking his place.