'Uncharted territory' as Tiger challenges for lead

Tiger Woods has made such a great recovery from last April's spinal fusion surgery that many might wonder why he did not have the procedure sooner.

But Woods said on Saturday he was not prepared to risk the operation until he basically had no other choice if he wanted to have a chance of living pain-free and playing competitive golf again.

"This is uncharted territory," Woods said after moving within one stroke of the third-round lead at the Valspar Championship in Palm Harbor, Florida.