Trainer Colin Tizzard has told of his shock at ruling out favourite Thistlecrack from next month's Cheltenham Gold Cup because of injury.
The nine-year-old will miss the rest of the season with a slight tendon tear.
"It was not great at all. We scanned him and the realisation he was out hit me for six," Tizzard told BBC Sport.
"I thought I was stronger than that. We're dealing with disappointments with horses all the time, but it hit me all day."
Thistlecrack had previously established himself as jump racing's new star with four wins from five starts in his first season as a steeplechaser.
On Boxing Day, the horse, ridden as usual by jockey Tom Scudamore in the silks of owners John and Heather Snook, became the first novice to win the sport's mid-season championship, the King George VI Chase at Kempton.
However, this week veterinary tests found the horse suffering from a tendon injury that although relatively minor brought his season to a premature end.
"Any horse when you have a setback is galling, but the bigger name they are I suppose the harder it is for a while," he said,
"The good part about it is that if you walked into the stable now, you would have a job to see which leg it is, it's that minute a tear [to the tendon].
"Hopefully we can get him back [for the King George defence] next Christmas and do it all again. "
Such an outstanding start to his career over steeplechase fences has ensured that Thistlecrack, already a champion over hurdles, had become the subject of considerable hype.
Regardless of his position in the reckoning for the Timico-sponsored Gold Cup, there'd been a feeling that the horse, with the breathtaking jumping style, could be the new kind of hero - in the mould of Kauto Star or Desert Orchid - that every sport craves.
Dorset-based Tizzard, a one-time dairy farmer who now has one of the most powerful strings in the country, found himself in a curious situation.
On the one hand, he'd lost the chance to saddle jump racing's most spoken-about horse in its top race, while on the other he also had under his care the Gold Cup second and the third favourites, Native River and Cue Card, who've subsequently moved up a notch in the betting.
I wondered how nervous Tizzard was phoning to break the news to the Snooks - retired farmers who named the horse after a field on their farm near Yeovil in Somerset - who'd inevitably got caught up in the hype like the rest of us.
He said: "As soon as we realised, I needed to make the call - there was no point thinking about it
"They were fine; the thing is that the horse wasn't dead, no one's died, and you need a bit perspective - it's a small tear - it's not life threatening or anything like that, he's just out for this season."
In contrast, calls to Garth and Anne Broom, owners - as Brocade Racing - of Welsh Grand National winner Native River, and to Jean Bishop, the octogenarian owner of 'people's favourite' Cue Card were that much easier.
And the vibes on the pair, just two of a string of likely Cheltenham Festival runners for the Tizzard team, are all positive.
The trainer said: "Native River has what it takes to win a Gold Cup, whether or not he does it this year. He is only seven and going the right way.
"Cue Card has been a fantastic horse for us - he's won the Champion Bumper and Ryanair at the Festival and was running a hell of a race [in the Gold Cup] last year before he fell.
"He won so strongly at Ascot [on his most recent start] and looks as well as he's ever been."
- The four-day Cheltenham Festival runs from 14 to 17 March. Commentary of all races on BBC Radio 5 live/Sports Extra.