USC running back Stefon Johnson was lifting weights Monday morning when he apparently lost control of the bar and it landed on his neck. He was reportedly spitting up blood and was taken by ambulance to the hospital, where he is undergoing surgery, according to the USC website. Chris Carlisle, USC's strength and conditioning coach, said such an accident was rare. "I've seen players have the bar slip and fall onto their chest, but never in my 25 years of coaching have I heard of someone dropping a bar on their throat," the coach said. Carlisle, who was within feet of Johnson when the accident occurred, said an assistant strength and conditioning coach was acting as a "spotter" for the player. Coach Pete Carroll called the incident "an unfortunate accident," adding that "our thoughts and prayers are with Stafon." Johnson has rushed for five touchdowns so far this season.