Eleanor Brennan, 21, died in Ocala on Saturday when her mount, Mr Barnabus, stumbled at a jump and landed on her.

Brennan sustained fatal head and chest injuries.

"It is always tragic when something like this happens," said British team manager Yogi Breisner. "My condolences go to her family and friends."

"She was a lovely, charming young lady and a good rider," he added.

Brennan was competing for the first time at the Florida International Three-Day Event and Ocala Fall Horse Trials, described as "the most challenging in the equine industry".

606: DEBATE Your reaction to news of Eleanor Brennan's death

Organisers said Mr Barnabus struck a gate while attempting to clear a fence and rolled over onto its neck, trapping Brennan underneath.

The fall saw 11-year-old Mr Barnabus die instantly.

In 2005 Brennan became one of the youngest competitors at the prestigious Badminton Horse Trials and has since established herself on the American eventing circuit.

She spent several years training and riding in Gloucestershire alongside some of the biggest names in British equestrianism, including Olympic champion Captain Mark Phillips.

Brennan also worked with five-time Olympian Nick Burton while she was said to be friends with the reigning Eventing World Champion Zara Phillips.

After studying equine business management at Hartpury college, Brennan sacrificed a promising riding career in Britain to take a job training horses and riders at a farm in Virginia.

Mike Etherington-Smith, sports director of British Eventing told BBC Sport that Brennan was not in contention for a place in the squad for next year's Olympics in Beijing but that she would almost certainly have been a candidate in the future.