As embarrassed officials launched an inquiry into Saturday's debacle and disappointed punters reclaimed their stakes, Carolyn McCarthy, 45, began celebrating a win of more than pounds 150,000.
Miss McCarthy, a nanny for Tommy Stack, the Irish trainer and former jockey who rode Red Rum to his third Grand National victory in 1977, said if the race had gone ahead she would not have won this year's 'Ten to Follow' competition, organised by the Tote, the state-owned bookmaker, and Racing Post newspaper.
Last November Miss McCarthy, who lives with Mr Stack and his wife and two children in Tipperary, in the Irish Republic, paid pounds 10 for two entries. Competitors pick 10 horses they think will perform well over the National Hunt season and are awarded points each time one of their choices wins a selected race.
Last Friday Miss McCarthy led the 72,600-strong field by five points after firsts at the Cheltenham Gold Cup and the King George VI Chase. But, because none of her 10 horses was in the National, the contest's final race, she had given up hope.
'There was a group of competitors as close as five points behind me. One of their horses would almost certainly have won the National and they would have overtaken me,' she said. She was 'absolutely bamboozled' that she had benefited from the fiasco. 'It is a queer thing. I entered for fun - just like the lottery - but when you win it suddenly becomes serious.'
Although glad the race was declared void, she added: 'As someone who has grown up around horses, I am very disappointed for the trainers. It's a whole year's work down the drain.' She will use some of the money to buy Mr Stack a horse because he helped to select her runners.
The Jockey Club said yesterday that it would act immediately to prevent a repeat of the fiasco. Interim measures would be introduced to improve race start and recall procedures, officials said.