Solwhit, one of the leading figures for some time in the ultra-competitive Champion Hurdle market, threw the race into an agonising confusion yesterday when a major doubt was cast over his participation.
The multiple Grade One winner who most recently won the Irish Champion Hurdle at Leopardstown, was as big as 29/1 on Betfair following the news that Charles Byrnes' charge had scoped dirty and may have to miss the opening day feature at next week's Cheltenham Festival.
The Co Limerick trainer said: "Things are very much in the balance with Solwhit as he has scoped dirty and we've put him on antibiotics."
Solwhit had progressed steadily through the ranks from last season and in bypassing last year's Festival he managed to land the Aintree Hurdle and the Champion Hurdle at Punchestown before a Cheltenham trail that saw him land three Grade Ones from four appearances.
His sole defeat came in a slow-paced renewal of the Fighting Fifth which was won by the million searching Go Native, a race in which Solwhit finished third.
Byrnes added: "The plan had been for him to travel over to England on Saturday morning but that will have to be put on hold now.
"We'll have to scope him again later in the week and see how it's looking."
Solwhit is no bigger than 5/1 with the bookmakers and was last night trading at just over 11/1 on Befair having been more than double that earlier in the day, but Byrnes is naturally very anxious over the coming days.
He added: "It's obviously very disappointing as he was never given any indication anything was wrong, apart from one cough.
"We're just going to see how he reacts to the antibiotics and make a late decision."
Betfair spokesman Tony Calvin commented on the fluctuation of the market after yesterday's big news.
"The Champion Hurdle has been one of the most volatile ante-post markets in recent years," said Calvin.
"Solwhit now becomes the fourth horse to deliver favourite backers a potential hammer blow, following the woes, setbacks and defeats that have befallen one-time market-leaders Hurricane Fly, Binocular and Zaynar."
Hurricane Fly was ruled out for the season after just one run when he was beat by Solwhit, while Binocular was ruled out but said to be back in some sort of contention late last week, and Zaynar was then turned over at long odds on at Kelso.
Last year's winner Punjabi never made the head of the market having taken time to come to winning ways, while previous Champion Hurdle winner Sublimity, who split Go Native and Solwhit in Newcastle and who would have relished Cheltenham's nice ground, was also ruled out over the weekend with a bang to the leg.
Two others who do still hold Champion Hurdle entries but are set to take up their other engagements are, of course, the Supreme Novices Hurdle favourite Dunguib and Mares Hurdle-bound Voler La Vedette.
The latter's trainer Colm Murphy was still not ruling out the Champion Hurdle although admitted that it would be very unlikely, while Philip Fenton remains adamant that Dunguib will remain in novice company next week.
Despite the fact that Solwhit became a major doubt, Fenton indicated that Dunguib will not make the step up in class next week but it would be a possibility at the Punchestown Festival if the seven-year-old was to justify his 'banker' description in the first race of next week's epic festival.
Watering commenced at Cheltenham yesterday and although likely to be boosted by the Solwhit news, trainer Noel Meade was not anywhere near as pleased to learn of the taps being turned around the Cotswolds.
While chasing the £1million hurdling triple crown bonus put up by WBX.com, Meade had initially sent Go Native across the water for some nicer ground but it looks almost certain to be good to soft with officials resolute to achieve that for the opening day.
Noel Meade said: "I'm sure a lot of trainers of soft-ground horses will welcome the news, but then there are those like us that don't really want it."
However, in winning the Supreme Novices Hurdle at the meeting 12 months ago, Go Native encountered the exact conditions the racecourse are bidding to achieve for next Tuesday.
"He handled it last year in the Supreme when it was good to soft and it had rained on the Monday night," said Meade.
"The danger is if they get it wrong and over water or it rains heavily overnight, you just never know."
Cheltenham's clerk of the course Simon Claisse said he is working to produce ideal jumping ground for the Festival but his plans for watering had to start later than anticipated yesterday due to frost and low temperatures.