He said Monday he still plans to play in the Hero World Challenge from December 1-4.
He committed to play in the Safeway Open last Friday and was scheduled to pair with National Basketball Association superstar Stephen Curry during Wednesday's Pro-Am.
Saying he is "not yet ready", the golfer withdrew from this week's Safeway Open tournament and the Turkish Airlines Open in November. In fact, even competing in his first event appearance, like his own Hero World Challenge, which is apparently still a possibility for his return, won't get me excited about anything.
Tiger Woods has withdrawn from this week's Safeway Open, delaying his comeback after 14 months out following back surgery. "Whether I can play depends on my continued progress and recovery. I'm close, and I won't stop until I get there", Woods said in his statement.
Five-time major champion Mickelson said last month he was looking forward to Woods's return. However, Woods made it evident with the language of his announcement that he could still back out of any or all of the tournaments.
Woods has been sidelined by serious back problems for a number of years, having undergone three operations during a 19-month spell.
"Let's be realistic", the four-times major victor told Reuters.
Woods has been limited to 11 starts since the beginning of the 2014-15 season, and did not play on Tour at all in the 2015-16 season. The Safeway Open is the first tournament in the PGA Tour's wraparound schedule. The expectation and nervous level has got to be nearly like when he played in his first L.A. Open when he was a kid.
Woods' record for the lowest 72-hole score in relation to par at The Open was taken by Henrik Stenson this year, the Swede's 20-under total at Royal Troon one shot better than Tiger's winning mark at St Andrews in 2000.
"I was ready to quit and a voice said to me, "It's not what you accomplish in life that really matters, it's what you overcome that proves who you really are, and proves the man".
"He's not ever going to be the old Tiger (but) I still think he can win, if he has the desire".