Tiger Woods ruled himself out of the Ryder Cup on Wednesday, saying he needs time to strengthen his ailing back.
The 14-time major champion missed the cut at last week's PGA Championship with back spasms, a week after he withdrew from the World Golf Championships event in Akron, Ohio, with similar trouble.
Even so, US Ryder Cup captain Tom Watson said Monday he would still consider making Woods a captain's pick for the team to face Europe in September -- if the former world number one was sure he was healthy.
"I have already spoken to Tom about the Ryder Cup, and while I greatly appreciate his thinking about me for a possible captain's pick, I took myself out of consideration," Woods wrote on his website.
"The US team and the Ryder Cup mean too much to me not to be able to give it my best."