The 54-year-old Austrian defeated Alexandra Ledermann of France on her Olympic bronze medal partner, Rochet M, and the American rider, Peter Leone on Crown Royal Legato. Both riders appeared to be heading for their second clear round until clobbering the final fence.
It was a disappointing contest for the British riders, with only Geoff Billington among the top 15 who contested the second round. As in Atlanta, he finished in sixth place on It's Otto, whose only jumping error came when he nudged the lowest pole of a triple bar.
The two Whitaker brothers and Nick Skelton dropped out with two errors apiece in the first round. Robert Smith retired the game but limited Mighty Blue after he had lowering four fences.
Michael Whitaker recorded his first success, and Britain's fifth, at this year's Monterrey International Horse Show when he rode Magic Carpet to win the Marcatel Classic on the closing day of the meeting at the Club Hippico la Silla.
Results, Digest, page 19