How the favourite's injury was first flagged on Betfair
The early warning system that is Betfair's ante-post exchange market started the alarm bells ringing over Thistlecrack's injury even as Colin Tizzard's vet was giving him the bad news.
When contacted by the Racing Post at 12.33pm Tizzard still had his vet with him, having scanned the horse an hour earlier, and the news was broken in a Racing Post tweet four minutes later.
Betfair suspended their Gold Cup market at 12.44pm and reported a total of £12,800 matched on Thistlecrack on Tuesday up until the news broke but only £174 in the seven minutes from 12.37pm, by which point the lay column was already virtually empty.
Punters and bookmakers alike have become used to monitoring Betfair's ante-post markets on big races for likely non-runners or change of running plans in recent years, with odds often drifting before withdrawals are publicly announced.
Money disappearing across the lay column on Betfair in the minutes leading up to the official announcement was noticed by bookmakers, although none of the firms contacted by the Racing Post reported seeing any unusual bets.
Nicola McGeady from Ladbrokes said: "We noticed there was a move on Betfair so we kept an eye on it but we didn’t see anything suspicious or take any bets so there were no alarm bells as such."
William Hill were also on the ball, reporting they suspended their Gold Cup market a minute after the Racing Post's tweet.
The biggest effect to Coral was a last-minute marketing panic as sponsors of the Tizzard stable rather than any flood of bets for other runners.
Simon Clare, head of Coral PR, said: "We were going to use Thistlecrack in all our marketing which needed to be done by Wednesday.
"On a personal and a professional level I feel desperately sorry for Tom Scudamore, Coral's jump racing ambassador, as we had priced him up at only 33-1 to win the Gold Cup and Grand National after his Haydock win at the weekend and to win a race his father Peter never won."
The cost of Thistlecrack's absence to ante-post punters is illustrated by the fact £330,000 of the near £1 million traded on Betfair's Gold Cup market since the King George was on the favourite.
However, Sky Bet, who went 8-1 about Thistlecrack after his Cheltenham Festival win last year and 7-2 after his November win, reported they had taken most money on him since going non-runner no-bet when he was 2-1 after his defeat by Many Clouds in the Cotswold Chase.
Bookmakers were in general agreement that the biggest loss of Thistlecrack's absence would be in the heaviest-betting final days into the race.
Ante-post punters, however, have been left to lick their wounds. They have already suffered deep cuts with Thistlecrack joining Coneygree, Don Cossack, Annie Power, Faugheen and Min in being ruled out through injury this winter.