Simple. A puss-filled horse tooth has spelled the end of Victoria Max-Theurer’s Olympic dressage dreams.

The Austrian’s 11-year-old horse, Abegglen NRW, had been behaving strangely in training and, while the Olympic opening ceremony was underway on Friday night, a health check and x-ray revealed a tooth infection. It would have been her fifth Olympic start.

“This news is a heavy setback for Victoria. We hope that Abegglen will feel better soon and that Victoria will continue on her path,” said Peter Mennel, of the Austrian Olympic Committee.

Max-Theurer’s teammates Christian Schumach and Florian Bacher will now compete only as individuals.

Today and tomorrow, the world’s best riders and horses in dressage, also known as “horse ballet”, will compete in qualifiers for a chance to win team and individual medals on July 27 and 28.

Germany’s Isabell Werth, the most decorated Olympian of her sport, and Britain’s dressage world number one Charlotte Dujardin, are hot medal contenders.