Woods complained of back and neck discomfort earlier this week which he blamed on a soft hotel bed and the world number one looked uncomfortable at times on Saturday at Liberty National.
"I just hung in there and that was a grind," Woods told reporters after the third round, in which three late birdies lifted him to a 69 that put him tied for fourth, four shots behind co-leaders Matt Kuchar and Gary Woodland.
Due to weather delays on Thursday that threw the tournament schedule out of whack, Woods and 39 other players had to return to the course early Saturday morning to finish their second round before the scheduled third round of play.
Woods had to complete five holes before heading out for round three. He finished up a two-under 69 and stood five shots off the pace at the halfway mark.
After sticking his approach shot for a one-foot, tap-in birdie at the first hole of the third round, Woods struggled with bogeys at the third and fourth holes.
"I got off to a sweet start. Stuffed it at the first and gave two right back at three and four and kind of just hung around, hung around, hung around, and had a nice finish," said the American, who birdied two of his last three holes.
Despite receiving treatment, Woods still seemed bothered by the back.
"It starts off great every day, and then it progressively deteriorates as the day goes on," he explained.
"Hopefully tomorrow it will be one of those days again and (I will) fight through it and see if I can win a tournament," added Woods, who has already won five times on the PGA Tour this year.
(Reporting by Larry Fine, Editing by Gene Cherry)
