Frankie Dettori has been ruled out for the season with a broken ankle after a fall at Nottingham.

Although an initial on-course prognosis suggested he had suffered only soft-tissue damage, X-rays subsequently revealed a break.

Dettori was due to partner leading Prix de l'Arc de Triomphe contender Treve at Longchamp on Sunday.

The unbeaten Treve will now be ridden by Thierry Jarnet, who rode the filly to victory in her first three races before she was sold to Dettori's new boss, Sheikh Joaan Al Thani.

Trainer Criquette Head-Maarek said Jarnet would be an able replacement.

"I have just spoken to Frankie and I have just spoken to Sheikh Joaan, who has agreed that Thierry Jarnet will ride Treve on Sunday," Head-Maarek said.

"He knows the filly very well and won the Prix de Diane (French Oaks at Chantilly) on her in June.

"It is bad luck for Frankie, but that is life in racing."