Tiger Woods withdrew from The Players Championship on Sunday with an injury that he fears might be a bulging disk in his upper back.
"I've been playing with a bad neck for about a month," Woods said.
After hitting his drive well to the right on the seventh hole, Woods called for an official. He hit his second shot and grimaced, then walked to the middle of the fairway to shake hands with playing partner Jason Bohn before leaving on a golf cart.
Woods had his head bowed for several minutes as he sat in front of his locker and other times kept his eyes closed before answering questions from a couple of reporters.
He said he first felt the injury before the Masters and plans to have an MRI next week. Woods said he has felt a tingling sensation on his right side down to his fingers.
It is the first time he has withdrawn from a tournament since the Nissan Open at Riviera in 2006, when he narrowly made the cut and withdrew from the final two rounds because of the flu.
Woods started the final round 10 shots out of the lead and was 2 over through six holes.
It was Woods' third tournament back from his five-month hiatus after a sex scandal. He tied for fourth at the Masters but missed the cut at Quail Hollow last week.