British riders will have their work cut out to keep the £60,000 Mitsubishi Motors Trophy at home, as a competitive international field for the 2011 Badminton Horse Trials, an important Olympic qualifier, is announced today.

Mark Todd, a triple winner, heads the overseas challenge for the world’s premier equestrian event, held over the Easter weekend; the 55-year-old New Zealander, who won team bronze at last year’s World Equestrian Games, is firmly back in his stride after an eight-year ‘retirement’ and has three horses entered.

His team-mate Andrew Nicholson, 49, another veteran, would also be a popular winner – he has completed Badminton more times (29) than anyone else – and compatriot Caroline Powell could do the famous double by following up her Burghley victory on the bouncy grey Lenamore who, at 18, would be the oldest horse to triumph.

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The Australians, Americans, Germans, French and Canadians all field strong contingents and if young rising star Sam Watson pulls it off, he will be the first Irishman to win since 1965.

British hopes rest on the victorious World Games squad: Mary King, who celebrates a quarter-century competing at Badminton; reigning European champion Kristina Cook, world number one William Fox-Pitt, who has a remarkable five horses to choose from, and Nicola Wilson, plus Pippa Funnell, another to make a dramatic comeback to the big time, and Piggy French.

The 2009 winner Oliver Townend, who endured mixed fortunes last year, is sure to give his elders a run for their money, as is the 2008 runner-up Lucy Wiegersma, and new mothers Daisy Berkeley, third last year on the evergreen Springalong, and Polly Stockton will be as competitive as ever.

For a full list of entries, and to book tickets for Badminton, which takes place earlier than usual on April 21-25, visit www.badminton-horse.co.uk