Riding Classic Moet, the 37-year-old managed to go clear in the show jumping phase and remain inside the time to ensure her previous points total of 28 stayed intact.

As reported by Horse and Hound, Price, who is the first female winner of the competition since 2007, was full of praise for her horse.

"I had lady luck on my side," said Price, who was top overnight after the cross-country.

"She is a deserving winner despite the luck today.

"It was so tight, I really thought anyone in the top 10 could have won it.

"I'm just so pleased with her and for her owner, Tricia Rickards.

"We haven't ever jumped a clear round on the last day, but sometimes dreams do come true and you have to believe it is possible.

"At 15-years-old it just feels like she is getting better and better.

"Each day we have pulled off what I hoped we would be able to achieve.

"Last night I told myself it was going to take a clear round to win, there's some very good horses behind me.

"Classic Moet is a good jumper, she tries, but is a bit unorthodox in her style, it doesn't come easy to her - just like everything else she does, she tries her heart out."

Price's win meant that Great Britain's Oliver Townend lost out on clinching the overall Rolex Grand Slam title in three day eventing.

Townend, riding Cooley SRS, also posted a perfect round in the jump but he required Price to slip up if he was to finish first.

The world number one eventually finished on a total of 33.1, 5.1 behind Price.

Townend's compatriot Rosalind Canter, who was making her debut at the competition, rounded off the podium with a total of 34.3.