Nicky Henderson has dismissed speculation about the well-being of JCB Triumph Hurdle market leader Sir Gino, insisting he is “100 per cent”.

The four-year-old was ultra-impressive when accounting for Burdett Road at Cheltenham on Trials day, since when he has been hot favourite to claim Triumph glory on Friday.

However, Sir Gino’s price began to drift alarmingly on Betfair on Saturday night, prompting suggestions he was under the weather.

His odds soon came tumbling back down, though, and Henderson said his charge is in fine spirits ahead of the Festival.

“He was in great form yesterday morning – I don’t know where this has come from, I really don’t,” the Seven Barrows handler told Racing TV’s Luck On Sunday programme.

“It’s just one of those things they love to throw at you just to test your mental agility, I think – it’s crazy.

“He schooled on Thursday and you wouldn’t see anything slicker. He had a nice piece (of work) on the last little bit he’s going to do. He doesn’t run until Friday…and he is 100 per cent, I can promise you, 100 per cent.”

Henderson also issued a positive update on Gold Cup hope Shishkin.

He added: “He’s in very good nick, I like to think. Shishkin is in very, very good form – we’re very happy, he’s come on a lot from Newbury I’d say.”

Meanwhile, Constitution Hill has been taking things easy since being ruled out of Tuesday’s Champion Hurdle.

“He hasn’t done much for the last week because the only thing to do is leave him alone and let him get over this,” said Henderson.

“We will take his blood again tomorrow morning, which will be comparable to last Monday’s one, and we just hope these figures keep improving. They’ll give me an indication just to when we can start to wander on with him.

“He’s absolutely fine in himself. He was down in the doldrums that week, after the gallop at Kempton, and he quietly over that weekend afterwards started to perk up a little bit, but we’ve done very little this last week.”