Britain were in second place after the dressage in the three-day event at the Georgia International Horse Park, 4.8 points behind the United States, with New Zealand, the favourites for gold, lying third just 7.8 points behind.
A fine performance from Karen Dixon on the lively Too Smart, the last of Britain's four riders, lifted spirits with a useful 43.60.
Dixon had to contain her mount's exuberance with two hours of careful preparation. She kept cool in the sweltering afternoon heat, and is looking forward to today's cross-country test. "It should suit Too Smart," she says. "He's small and nippy, and the turns will help him to concentrate."
Dixon followed world champion Vaughn Jefferis, on Bounce, who was disappointed with 47.40 penalties, but quickly refocused on the cross-country challenge, saying: "It's huge. The hills will have as much influence as the heat."
Dixon's test was especially valuable after Britain's third team rider, Gary Parsonage, scored 62.60 on Magic Rogue.
With little experience, Parsonage was unfortunate to follow New Zealand's multiple medal winner Vicky Latta into the arena. Latta rode an immaculate test on Broadcast News, for just 41 penalties, strengthening her team's position.
Magic Rogue lacked the movement and balance of Broadcast News, and became tense towards the end of his test, especially in the second walk. "He hates walking," Parsonage said, "He thinks dressage a waste of time."
Yesterday began with the sad news that Matt Ryan, Australia's Olympic champion, has withdrawn from the event. Hinnegar, his horse, has bruised a foot and it was too late to call upon his reserve horse, Alater Pedis, for the individual event. Gillian Rolton, filled Ryan's team place with Peppermint Park, scoring 57.00 in the dressage.
"Horses are always at risk when they're working this hard," Ryan said. "We still have a stronger team than when we won in Barcelona, and it's on cross-country that we shine. We're in with a good chance."
Bruce Davidson, going third for the United States, had an excellent test on Heyday, scoring 42.60 which, combined with Karen and David O'Connor on 36.60 and 40.80, gave them the lead.
With today's cross-country looming large, competitors are cautious about the course, but less concerned about the heat."Everything possible has been done to help us," said Davidson. "It's down to us, the riders, now."
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