Nicky Henderson is juggling a range of emotions as Altior prepares to take on Cyrname in a mouthwatering showdown at Ascot on Saturday.

Unbeaten in 19 races over obstacles, Altior has carried all before him in the two-mile division - but is setting out on a different path this term, with a tilt at the Ladbrokes King George VI Chase over three miles the big aim in the first part of the season.

Henderson first wants to try him over the intermediate trip of two miles and five furlongs in the Christy 1965 Chase.

Not only must Altior answer stamina questions, in opposition is set to be the only jumper in training with a higher official rating - the Paul Nicholls-trained Cyrname.

Henderson said: “He has been in great form and his work has been excellent. It is going to be a fascinating clash and it will sort one thing out - who is the top-rated horse.

“It is a big ask - because of the step up in trip you are asking a big question. If you had seen him work last Friday, he doesn’t look like a horse that is going to stay, as he has got such a ridiculous amount of speed.

“His jumping is so quick and slick, so hopefully his jumping will help him relax, which I hope he does. If he goes into attack mode it will get very aggressive early on.

“It’s going to be interesting, as we could all do with a dry week - Altior could. Let’s hope the race lives up to its billing. It’s a big test for both of them.”

Henderson could feasibly have been quite content to have kept his winning run going over two miles, but outside pressures appear to have played a part in him doing something different.

He said: “Why step up in trip? It’s media pressure, thanks guys. Everybody says it is boring watching him go round over two miles, so let’s show us what he can do.

“If you saw him last Friday, you would have thought this can’t be the right thing. It’s just crazy, he has got so many gears and you can’t believe he is a genuine stayer. If he is a stayer, he is the most remarkable horse I’ve ever seen.

“The timing of this race is right. It’s lovely you have two horses like this and people are building it up to be something quite exciting, that might be worth going to watch. It’s the sort of clash you do want.

“I think it is exciting. It is good stuff and you would rather be involved than not. We will be the ones slightly a bit more jumpy than everyone else. We are putting on the show.

“If he is a true champion he has got to be able to do it over a variety of distances and this is where we are testing it. There are a lot of questions to be answered and a lot to prove.

“Paul and I have got more to lose and the two boys riding (Nico de Boinville and Harry Cobden) have got a big job.”