Tiger Woods will not be in the United States team for the Ryder Cup next month after withdrawing himself from consideration for a captain’s pick due to injury.

The 38-year-old failed to qualify for the team outright and has now informed the PGA of America and Ryder Cup captain Tom Watson that, after playing just four tournaments on his return to action following back surgery, he does not wish to be considered for one of the three remaining places.

Woods has struggled with personal problems and a series of injuries since winning his most recent major championship at the 2008 US Open, with a back injury the latest to disturb his career.

Woods underwent back surgery on March 31st and has now admitted he will not be fit to participate at Gleneagles.

“While I greatly appreciate Tom thinking about me for a possible captain’s pick, I must take myself out of consideration,” Woods said in a statement on www.pga.com.

“I’ve been told by my doctors and trainer that my back muscles need to be rehabilitated and healed. They’ve advised me not to play or practice now.

“I’m extremely disappointed that I won’t be ready for the competition.

“The US Team and the Ryder Cup mean too much to me not to be able to give it my best. I’ll be cheering for the US Team. I think we have an outstanding squad going into the matches.”

Woods‘ decision to rule himself out was a wise one given his struggles since undergoing back surgery in March, but it also raises fresh concerns over the former world number one‘s playing future.

Questions will undoubtedly be raised as to whether he decided to return to competition too soon after having a procedure to treat a pinched nerve in his lower back.

Though he says he has always recovered quickly from surgeries, he looked tournament rusty and a shadow of his former self in his last four PGA Tour appearances, twice missing the cut and once withdrawing midway through the final round.

At the age of 38, Woods is perhaps also paying the price of long hours spent on the range and in the gym, where he has always pushed himself punishingly hard.

The 14-times major winner has had four knee surgeries over the years, along with a string of other injuries, and undergone several swing changes in an attempt to limit the more severe effects of the golf swing on his body.

He famously won the most recent of his major titles in a playoff for the 2008 US Open at Torrey Pines where he defied doctors‘ orders to compete after suffering a double stress fracture in his left shinbone two weeks before the tournament.

Yet former PGA Championship winner Paul Azinger believes Woods‘ problems this year are not purely physical, and that perhaps he has spent too much time on yet another overhaul of his swing.

“He has gone from the artist to the engineer,“ Azinger said during last week‘s PGA Championship while commentating as a television analyst for Golf Channel.

“It is difficult to watch a Vincent Van Gogh paint by numbers. We want to see Tiger come back and get all of this stuff out of his head.

“The golf swing takes a second and a half. What is running through his head in a second and a half that has caused him to lose face and path awareness?

“Something is happening in the strongest and greatest mind that golf has ever known that is different, and he has got to fix it. It is not just physical.“

Woods missed the cut at last week‘s PGA Championship, only the fourth time he has done so as a professional in the majors, having pronounced himself fit to compete on the eve of the tournament.

He suffered a different back scare during the previous week‘s Bridgestone Invitational, but said that was resolved after his physiotherapist popped back his sacrum (a bone at the base of the spine), which had loosened after he landed awkwardly in a bunker.

However, a similar problem occurred before Woods teed off in the PGA Championship second round, forcing him to restrict his backswing and rely on timing, a combination that left him a distant 15 strokes off the lead by the time he finished.

Butch Harmon, who previously worked as a swing coach for Woods, said he should have quit in that second round.

“I was surprised he played the back nine. He looked really sore on the front nine; he looked like he was in a lot of pain,“ Harmon said during a Sky Sports telecast.

“I think Tiger wanted to show, ‘I came here to play, I‘m going to finish my round‘. I hope he goes home and gets healthy.”