Kauto Star was dramatically beaten a short head after being remounted following a fall at the second-last in the Weatherbys Bank Novices Chase at Exeter yesterday.

The 2 to 11 favourite was well clear of Mistral De La Cour when he hit the top of the fence and buckled on landing, pitching Ruby Walsh out of the saddle.

Walsh wasted no time in getting back on top, but he did not even try to get his feet back in the irons as he set off cowboy-style in pursuit of the new leader.

Eight lengths behind at the final fence, Kauto Star put in a strong challenge on the run-in, but he failed by inches to get back up.

The Lavinia Taylor-trained Mistral De La Cour (20 to 1) took the honours in the hands of Andrew Thornton with Goldbrook, the only other runner, failing to finish.

Kauto Star remained unchanged at 5 to 2 favourite for the Irish Independent Arkle Challenge Trophy.

Trainer, Paul Nicholls, said: "We won't rule anything out as far as having another run before the Arkle is concerned. My first reaction is that we don't need to, as it's only five weeks away and he is a brilliant jumper.

Walsh said: "I was heading straight on down to the victory and keeping something for the Arkle, I suppose. It was a bit my own fault. He was running a bit quick at it, but if it was more competitive and there was something coming at me, he might have given me something good and long.

"He clipped the top and pitched out on his head. I suppose it's better done today than at the second-last in the Arkle.

"He jumped magic all the way - that was the first he got in deep at. It's all a learning curve with novices so it is better that he learns here than at the Arkle. He's a very good horse."