Zara Phillips has been forced to pull out of the Olympics after her horse was injured in training.

The 27-year-old royal, who is the world champion three-day eventer, was tipped to win gold at the Beijing Games this summer.

But since she and the gelding Toytown were jointly selected for Great Britain's eventing team, his injury means she must also withdraw.

Zara Phillips jumps Toytown in Rome in 2007. The pair have pulled out of the 2008 Olympics just weeks before the Games began

The almost telepathic relationship between an Olympic rider and horse means switching to another mount is impossible.

Last night, Miss Phillips said: 'I am very disappointed not to have the opportunity to ride at the Olympic Games and feel that Toytown deserved his chance to go.

'However, with horses these things happen and we still have a very strong team. I wish them every success.'

More time together: England rugby international Mike Tindall and Zara Phillips, pictured at the Cheltenham Festival

Four years ago, Miss Phillips – who is 11th in line to the throne – missed the Athens Olympics as Toytown was injured.

She may well have a chance to represent Great Britain at the London Olympics in 2012. B

ut that hope is likely to be of little consolation at present. On Monday, she had voiced her fears that the pair would not make it to the event, which will be staged in Hong Kong.

'The next two months will be very nerve-racking because the horses can do stupid things and ruin their chance of going out there. The horses have got to compete before they go out there.

'You can't wrap them up and put them in a box and leave them. Now I'm in the team, the important thing is to get on the plane.'

But during training with Toytown on Tuesday, in Gloucestershire, a check-up revealed the injury.

Within hours, he was declared unfit for the Games. Details of the injury have not been revealed, but it is hoped he will recover.

Miss Phillips was voted BBC Sports Personality of the Year two years ago.

Her parents, the Princess Royal and Captain Mark Phillips, both represented Great Britain at the Olympics.

Zara gives Toytown a kiss before the competition in Rome last year