Foinavon: The Story of the Grand National's Biggest Upset, was honoured at a reception hosted by Castleton Lyons - a horse racing stable and breeding business in Kentucky, United States.

Owen was awarded $10,000 (£5,900/€7,200) and a Tipperary crystal trophy in the form of the farm's landmark stone tower.

Foinavon raced in the 1967 Grand National as a rank outsider, with odds of 100-1.

The horse, ridden by jockey John Buckingham, made hay when the rest of the field was caught up in a melee at the 23rd fence and went on to win.

That fence was named after Foinavon in 1984.

David Owen's book Foinavon: The Story of the Grand National's Biggest Upset has won the Tony Ryan award ©Amazon

"As a non-horse racing specialist retelling a British story, I was stunned to receive this award," said Owen.

"It must be true what they say about everyone loving an underdog.

"I'd like to thank everyone who helped me on the book and also Castleton Lyons for their kindness while I was in Kentucky."

Racing enthusiasts joined political figures, academics and fellow authors at the reception where Owen was named the winner of the eighth Tony Ryan Book Award.

The two other finalists were Shelley Lee Riley, a trainer and jockey who documented her 1992 American Triple Crown in Casual Lies: A Triple Crown Adventure, and Dorothy Ours for her historical look back at the 1938 Grand National winner in Battleship: A Daring Heiress, A Teenage Jockey, and America's Horse.

Each finalist received $1,000 (£595/€720) and a crystal trophy.

The award was established by Ryan in 2006 to recognise writing in thoroughbred racing.

He died later that year.

The panel of judges included Kay Coyte, Washington Post-Bloomberg News Service managing editor, and Patrick Smithwick, a lifelong horseman.

To buy a copy of the book click here.