Spaniard Ballesteros has battled with back problems

The 48-year-old, who won the second of his three Open titles at St Andrews in 1984, has not played competitively since 2003 because of injury problems.

Organisers have confirmed Jose Maria Olazabal, who had failed to earn a qualifying place, will replace him.

"I hope to be in shape soon but I'm not going to force it too much," he said.

Ballesteros also seems certain to hand over the playing captaincy for the Seve Trophy in County Durham in September.

But he said that despite his injury problems, he had no plans to retire and would be at St Andrews for a dinner to mark Jack Nicklaus' Open farewell.

"I have no plans to retire and that I will be at the Open, where I will attend the Past Champions dinner on Tuesday, where I will very much look forward to seeing my good friend Jack," he said.

"The back is always my main worry, it is what has been bothering me for a long time.

"My back and knee are progressing but not as fast as I would like. I'm practising, mainly in Pedrena, no less than 20 hours a week.

"I'm practising carefully every day and doing rehabilitation exercises.

"Unfortunately, I don't seem to be in command. My body tells me what I can and can't do."

Ballesteros has enjoyed a special relationship with The Open since he finished runner-up at Royal Birkdale in 1976, aged just 19.

Three years later, at Royal Lytham, he lifted the Claret Jug following a three-stroke win over Ben Crenshaw and Jack Nicklaus.

He claimed two Masters' wins before his second success at The Open, in 1984, and four years later a six-under-par final round of 65 helped him claim a third title, at Royal Lytham.