Andrew Hoy, of Australia, a triple Olympic gold medal-winner and most experienced rider in the 81-strong field, held a slender lead on his 2006 winner, Moon Fleet, from Ruth Edge, of Britain, on Muschamp Impala after a highly competitive dressage phase of the Mitsubishi Motors Badminton Horse Trials yesterday.

Two Britons, Lucy Wiegersma, on Shaabrak, and Matthew Wright, on his new ride, If You Want, lie third and fourth but only five points separate the top ten riders as the competition moves on to today's cross-country phase, in an event that few believe will be won on the dressage.

Zara Phillips, the world champion, who said before her test on the quirky Ardfield Magic Star that “he does what he wants in the dressage”, was sitting on a time bomb and did well to contain him. They are 76th. But Phillips, who is sixteenth on her first ride, Glenbuck, was philosophical. “He's very insecure,” she said. “He used to do a lot of standing up on his hind legs; at least he stayed on all fours.”

Hoy, 49, who first competed at the event in 1979, had a blip at the beginning of his test - when Moon Fleet jumped up and down in the first halt - but was quickly into his customary rhythmic stride. Edge, winner of the British Open in 2006, is a noted performer in this phase.

The order is likely to change significantly today when the riders tackle one of the strongest cross-country courses of recent years. “The questions start at Fence 1 and continue to the end,” Hoy said. Phillips, who walked the course with her father, described it as “serious”, particularly Huntsman's Close (Fences 5 and 6) and the Blue Cross Roundtops (12). Wiegersma, who has competed regularly since 1999, described it as “the biggest, most difficult Badminton” she has seen. Wiegersma at least knows that, in Shaabrak, who was seventh in 2006 and seventh at Burghley last year, she has one of the most consistent cross-country horses. Others among the leaders have concerns.

Moon Fleet has been sidelined with injury and this is only his second start in 12 months. Edge's Muschamp Impala was out of competition for two years with a tendon injury and he returned last summer only to fall at Pau last autumn.

Pippa Funnell, a three-times winner of the event and joint seventh overnight, had a fall on Ensign in her last attempt at Badminton two years ago. “He's had his critics,” she said of the former racehorse, “but people forget how long it takes to produce a horse to this level.”

William Fox-Pitt on Tamarillo, the winner in 2004, is eleventh. He, too, has a point to prove. Injured last year, the part-Arab gelding, 14, has not competed in a three-day event for two years. Fox-Pitt's hopes of riding him at the Olympic Games depend on his performance today.

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