"It's probably going to be a month or two," Woods said at an event Monday night in New Jersey where he promoted a new line of Nike weighted clubs with Rory McIlroy. "I just need to get strong. It's one of the things that when I took that fall at Firestone No. 2, I hadn't done any agility work, so that's part of the deal."
On Aug. 3, Woods withdrew from the final round of the WGC-Bridgestone Invitational after injuring his back while falling into the bunker on the second hole. Woods went on to play in the PGA Championship but missed the cut in a major for only the fourth time in his career.
Last week, he removed himself from Ryder Cup consideration, saying doctors had told him not to play or practice. He said his next tournament would be in December at the World Challenge, which benefits his foundation.
Woods had back surgery in March to relieve pain from a pinched nerve. He subsequently sat out for two months.
His best finish this season was at the WGC-Cadillac Championship before the surgery, when he finished tied for 25th. He has earned $122,272 this year, a career low.