Laura in dreamland on Town Moor

AS Laura Mongan made history by becoming the first woman to train the winner of the St Leger in the 240-year history of the world's oldest Classic, she whispered to Harbour Law's jockey George Baker on the Doncaster victory podium: 'I can't believe it. Is it a dream?'

Jockey George Baker and trainer Laura Mongan celebrate after their victory with Harbour Law in the Ladbrokes St Leger Stakes.

“No it’s not,” said Baker as he, too, shook his head in disbelief after a dramatic race that saw odds-on favourite Idaho unseat jockey Seamie Heffernan before this unlikely 28-1 outsider reeled in both Ventura Storm and Housesofparliament in the final strides.

More significantly, this was another heart-warming win for Flat racing’s underdog. Jackie and Nick Cornwell are unheralded owners; six-foot tall Baker is a farrier’s son who worked another miracle just to make the 9st 1lb weight and Mongan has just 20 horses at her Epsom stables which she runs with her husband Ian, who used to ride for the late Sir Henry Cecil.

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The Mongans might now be forgiven by their daughter, who spent her seventh birthday in the loving care of relatives while her parents drove the horse box to Doncaster for the day of their lives.

They only acquired Harbour Law from Jo Crowley’s yard at the beginning of the year. While the trainer had many sleepless nights fretting over whether to run this £20,000 horse in such an illustrious contest, her vigilant husband said he was leaping out of bed in the middle of the night at the slightest sound because he was so worried about the horse’s well-being.

Now they have rewritten the record books. Not only was this Baker’s first Classic but Mongan became the first woman to saddle the winner of one of Britain’s five Classics since Pam Sly’s Speciosa won the 1000 Guineas a decade ago. Surprisingly, Harbour Law was the first Epsom-trained horse to win a showpiece race since Right Tack won the 2000 Guineas in 1969 for John Sutcliffe junior.

“I wouldn’t say we were shocked, as we felt he had every right to be there, but you just don’t even imagine what it would be like to win,” said the winning trainer.

“I don’t think he’ll run again this season. Nothing is set in stone and we still need to have a discussion about it, but I think he’s probably done enough. He’s a horse who is still improving and we’ve always felt he’ll be a better horse next year.”

Yet her husband, who won York’s 2011 Juddmonte International on Twice Over, was quick to hail the influence of the aforementioned Cecil, who passed away in 2013.

“Henry Cecil sat me down three or four years ago and told me that good horses make good trainers and jockeys and that is exactly what happened today,” he said.

“He is a good horse. We were lucky that he came into our yard and all you have to do is feed them well and train them well and they’ve got engines and take you to special places. This horse has taken us to the St Leger – a Classic race.”

It will be clearly prudent to follow Rivet after the William Haggas-trained two-year-old wore down Thunder Snow to win the Group Two At The Races Champagne Stakes on Town Moor.

Not only does this race provide a clue to next season’s Classic contenders but the horse runs in the colours of The Starship Partnership which only tells part of the story.

They are made up of the winning trainer’s father-in-law Lester Piggott, who bred Rivet’s dam Starship, John Magnier and Michael Tabor from Ireland’s Coolmore stud and Des Scott, a 87-year-old South African. “I’m pleased to say they leave it to us, which is fantastic,” said Skipton-born Haggas.

The win was the first leg of a four-timer for jockey Andrea Atzeni, who was the leading rider at the St Leger meeting with a remarkable eight successes – six clear of nearest pursuer Oisin Murphy. However, Saturday’s crowd of 26,577 was the lowest since 2011 and this led to the meeting’s overall attendance falling from 65,425 in 2015 to 60,015.