Bookmakers were floored by "painful" Cheltenham Gold Cup day results as four of the big favourites won.
Punters celebrated a stretch of well-backed winners – including the big race hero A Plus Tard. Sent off the 3-1 market leader, the tough chaser helped earn Rachael Blackmore a place in the history books.
As he raced 15 lengths clear, the 32-year-old became the first female jockey to win the Festival feature. Vauban (13-8f), State Man (11-4f) and Billaway (13-8f) also headed the betting for their respective races – and they were part of an amazing five-timer for Willie Mullins.
"It’s all gone the punters' way," said William Hill's Tony Kenny. "When you have four big-name favourites winning on Gold Cup day and a jolly winning the big race itself, it’s going to be painful.
"Vauban, A Plus Tard, State Man and Elimay were also horses that had been wrapped up in huge-priced multiples, some of which have settled at monster odds and left a number of customers celebrating six-figure wins."
Willie Mullins set a new record with ten wins for the week overall.
Betfred spokesman Matt Hulmes said: "Willie Mullins has caused chaos on the trading floor today and ensured we have done our conkers. It was neck and neck in the bookies v punters battle going into Gold Cup day but Willie's winners have ensured a winning festival for the backers.
"Couple that with the punters' darling Rachael Blackmore striking gold on A Plus Tard and it was already a nightmare before Billaway and Elimay."
Nicola McGeady of Ladbrokes added: "Rachael Blackmore has done it again. Not only has she made Gold Cup history but she has also made it a day to remember for delighted punters, and a day to forget for the bookies.
"Her mount A Plus Tard was by far the best-backed horse in the Gold Cup, having been smashed into favouritism early this morning. After a tricky three days for punters they certainly got revenge today and have ended the week on a high."
Two of the seven races were won by horses at longer prices.
The Nice Guy (18-1) took the Albert Bartlett, while Banbridge (12-1) prevented further success for backers of the fancied horses.