Who would have thought such drama could unfold around the greatest certainty Cheltenham has seen in over 30 years? Everyone supposed Istabraq was a dead cert for today's Smurfit Champion Hurdle, but maybe that's the problem. Racing has its way of kicking certs in the teeth.

Except in Istabraq's case fate seems to have kicked him on the nose. The trickle of blood discovered in his left nostril yesterday evening by the Ballydoyle team at the racecourse stables is probably nothing. But on the eve of a tilt at a third successive Champion Hurdle this could have been done without. Speaking from Ballydoyle last night, Aidan O'Brien revealed that such an occurrence had happened once before when the famously excitable Istabraq was moved from one box to another at his home stable.

"We scoped him and found nothing. It was purely in his nose. The vets will have a look at him in the morning, but we will not be able to scope the horse so close to the race," O'Brien said last night.

"Hopefully, this is only in his nose as well and not further down. As we know he is an excitable horse who is very fresh and well and ready to race. Maybe the excitement of everything caused it.

"If he runs we won't know what effect it has had on him until after the race. The race will be the test and we have a decision to make," added O'Brien.

Should he get the go-ahead, he is set to become just the second Irish horse to complete the treble, a fact acknowledged by the man who poses the biggest threat to Istabraq's bid for glory.

Dermot Weld, who runs the Michael Smurfit-owned novice Stage Affair, is under no illusions about the task facing his six-year-old.

"As a realist, I think it's illogical to expect Stage Affair to beat Istabraq," said Weld yesterday before news of the dual champion's mishap hit Cheltenham like a bombshell.

"Istabraq is the best hurdler I've ever seen, a hell of a horse who has proved himself a great champion."

The Curragh trainer added that the decision to tackle Istabraq was influenced by a number of considerations, including Tony McCoy's availability and the Smurfit's sponsorship of the race but also the desire for Stage Affair to learn.

"He is far from the finished article, both physically and technically, and we feel he will learn more in the Champion Hurdle. If he does that he will be a serious challenger to Istabraq next year. But while everyone expects Istabraq to win, if you take that to its logical conclusion then he should get a walkover. And a lot can happen in racing, so you never know," added Weld.

Up until last night's late scare, O'Brien was happy with the horse's preparation and condition. "Every single horse in the race is a potential danger and he also has to get there in one piece. So far, so good but you never know what will happen," he said, not realising hours later his horse would be fighting for his place in this afternoon's line-up.

O'Brien's other perennial Champion Hurdle runner is Theatreworld, who could set his own remarkable record by finishing runner-up in the race for four successive years.

As a five-year-old, the other Irish runner Balla Sola faces a difficult task, but did beat Theatreworld at Gowran Park last time out. The best of the home team appears to be Dato Star, who has won at the Festival before but whose chance seems to be evaporating with every drop of moisture that leaves the drying track. "If it had been very soft it would hinder some of the others and that would be in his favour," said his trainer Malcolm Jefferson.

But it's hard to get away from Istabraq's quality. The professionals almost unanimously think he'll win, the bookmakers all think he'll win and now it's up to the horse. Don't expect Istabraq to disappoint.