The Prix de l'Arc de Triomphe betting market was thrown into confusion following some unexpected turn-ups on a muddy Longchamp track yesterday.

Dream Well, the French and Irish Derby winner, was displaced as Arc favourite after a lacklustre third in the Group Two Prix Niel. The favourite, clearly ring rusty, was unable to raise his game in the mud and was beaten 111/2l lengths into third by Sagamix.

Cash Asmussen, Dream Well's rider, said: "I wasn't hard on him although I made him work to make sure he got third and to make him know that he was in a race. He wasn't trained for today and I still have maximum confidence in the colt."

Sagamix, absent since the spring, was promoted to 4 to 1 Arc favourite after beating Dream Well's stablemate, Croco Rouge, by a length and a half.

Roland de Longevialle, racing manager to winning owner JeanLuc Lagardere, explained: "Nothing sinister should be read into Sagamix's absence. His trainer, Andre Fabre, has simply let him grow into his frame. Now for the Arc."

Godolphin's highly regarded Sea Wave, the second favourite, veered left as the stalls opened unshipping Frankie Dettori. The Arc, however, still remains on the agenda.

The Group One Prix Vermeille was won by John Dunlop's 10 to 1 shot, Leggera, who is most unlikely to be supplemented for the Arc, according to the trainer.

John Oxx's Irish Oaks winner, Winona, was a disappointing ninth of the 11 runners.