Tiger Woods likely to fall to No. 59

Tiger Woods will likely drop to his lowest world ranking in nearly two decades after withdrawing from the Farmers Insurance Open on Thursday.

With the release of the Official World Golf Ranking projections Friday morning, the calculations tentatively put Woods at No. 59, which would be his lowest spot since he won the first of his 79 titles on the PGA Tour at the Las Vegas Invitational in October 1996.

The weekly rankings will be officially released Monday.

That puts Woods in danger of missing this year's first World Golf Championship event, the WGC-Cadillac Championship -- to be held at Doral in early March. He would have to get inside the top 50 in the OWGR after the Northern Trust Open on Feb. 19-22 (which he isn't expected to play in) or after the Honda Classic, his next expected appearance (Feb. 26-March 1), to qualify.

The only other WGC for which Woods didn't qualify was the HSBC Champions in 2011.

While playing his 12th hole of Round 1 on Thursday at Torrey Pines' North Course, Woods said the back pain that caused him to withdraw started after fog delayed the start of his round.

"It just never loosened back up again,'' Woods said Thursday. "And when we went back out, it just got progressively tighter.''

Coming into Torrey Pines this week, Woods had dropped to No. 56 in the world after just his 13th career missed cut worldwide at the Waste Management Phoenix Open. The 82 he shot in the second round there at TPC Scottsdale tied the highest score posted by any player in a PGA Tour event this calendar year.

The Associated Press contributed to this report.