It's a little more than five months since Harriet Graham slipped between the wheels of her horsebox in an accident which broke her pelvis. She had gone to check on the welfare of the driver of a Land Rover stuck in a hedge on the opposite side of the road. Graham thought the man was having a heart attack but it transpired he was searching for his mobile phone in the well of his jeep. When Graham took a step back, she walked in front of the horsebox which was reversing back down the road.

That meant plenty of painkillers and rest. It was time off that she found difficult to cope with but her staff at Stripend in Jedburgh soldiered on without her during her period of recuperation. Graham – who sends out the favourite in today's rearranged Scottish Grand National at Ayr – says she is fully recovered now but suggests she was more of a hindrance than a help during her convalescence.

“I was an armchair boss which probably wasn't very nice for them [the staff],” she recalls of the period immediately after November's “stupid” accident. “I was bored and I was going up into the yard on my crutches but not able to do anything – that was probably more challenging for them than it was for me. I think they were wanting me to just stay in the house. I was in quite a bit of pain and in a better place not to interfere – they all just took it over and it all carried on.”

That horrendous start to the season will be a distant memory should Aye Right – one of nine Scottish horses in the race – finally prevail for Graham after a series of placed finishes in prestigious handicaps in which he made plenty of running but was beaten in the home straight. He was third in the Charlie Hall at Wetherby and second behind last week's Grand National hot favourite Cloth Cap in the Ladbrokes Trophy before Christmas. More recently, he has placed behind Takingrisks, the 2019 Scottish National winner, in the Sky Bet Chase at Doncaster, and at the Cheltenham Festival following home Vintage Clouds – with whom he will renew rivalries at Ayr – and Happygolucky, for third place in last month's Ultima Chase.

“He's a really tough little horse,” says Graham. “You would say – if you were to criticise him slightly – he is one-paced, it's a really good pace and it breaks other horses' hearts because it is a similar pace all the way round, hence him being a little bit vulnerable to a quicker finishing horse. We don't have any subtle tactics with him, it's just run your race, get your rhythm – and Callum [Bewley, his regular jockey] does that really well on him – and go for it.”

Those near misses all came at or around the three-mile mark and thus Graham hopes the extended distance of four miles will suit at a course where Aye Right has won twice over hurdles.

“He is a really good – touch wood – jumper and he does warm up to his jumping. That's why we're hoping the four miles might be the trick for him. He's always finished pretty fresh but we won't actually know that until Sunday afternoon, will we? We might actually find that he doesn't stay or his jumping goes to bits over a distance.

“We know about Vintage Clouds, there's other front-running style horses, but you just don't know how the race is going to pan out. To be placed would be fantastic, to win it would be wonderful, it really, really would.”

Graham, it seems, is possessed of all-too rare traits in an often cut-throat sport: easy-going humility and refreshing honesty so when she admits she was once “a bit of a hippy” it's not entirely a surprise.

Most people involved in horse racing come to it early and Graham, who combines training with her day job as clerk of the course at Hamilton Park, was no different even if she did take a circuitous – some might say unconventional – route into the sport. She says she could ride a pony before she could walk. Her mother was a trainer of point-to-pointers and would take her out on Dartmoor on a daily basis but by the time she left school she wanted to see the world beyond Devon.

“I went travelling for about three years and was a bit of a hippy, to be honest, I was meant to go for a year and, I don't know, it just extended. I went to Australia, I was in New Zealand and places like Afghanistan and Nepal. Then I came back and went to college. I was a photographer for a while for the NHS; then got a job in racing as a photographer for RaceTech and then I got into clerking. In that time we [her and husband Rob] had moved to Scotland, bought a place with a little bit of land and got back into point to point and that's where it [the training] came from. We love doing it, it's never been about trying to make it into a business. To do that you have to go bigger than what we are and I think that might take part of the pleasure away from it. We've got a really good head girl, we've got really good people who work hard and they fill in the gaps – they probably don't need me. We're a tiny trainer, Geoff and Elspeth Adam are fantastic owners and have supported us all the way.”

Her small-yard status – presently Graham oversees eight horses – has hardly acted against Aye Right but he will have to overcome some pretty strong trends to win – favouritism falls heavily on the shoulders of Scottish National contenders, so too extra lead in the saddle pad. The eight-year-old sits near the top of the handicap and carrying the weight of a nation doesn't tend to help either with Merigo (2010, 2013) the only Scottish horse to triumph in the last 39 years.

“It's easier to go into a race with a 20/1 shot and surprise everybody,” says Graham. “We obviously want desperately to win but if we don't it will not be the end of the world. As long as the horse comes back safe and well, we will be quite content. I am a realist when it comes to horses – they are not machines. The stats for top weight and Scottish-trained horses are not great in the Scottish National.”

While Graham might be the “most-English” of all her fellow Scottish trainers there can be no doubting the Tartan credentials of Aye Right. He's as tough and hardy as shipyard rivets with a name that plays on the kind of self-deprecating humour that has become a national pastime. But around the yard he's known simply, and affectionately, by a name that's even more quintessentially Scottish.

“I asked the owners what we should call him and they just said 'Jock',” says Graham. “It's a good Scottish name, isn't it? It stuck with him. It sounds a bit mad when I'm shouting 'Come on, Jock' [in races] and people don't know who I am talking about.

“I have lived up in Scotland for longer than I lived in England and Geoff has had horses trained in Scotland all his days, all the staff are Scottish, in our local area in the Scottish Borders he's got a hell of a following and they would be made up if he won.”

Whatever happens today as Graham bids to become the second woman to win a National in a week following Rachel Blackmore's success at Aintree, she will remain grounded and puts her carefree manner down to those years of wanderlust “a very, very long time ago”.

“I think it made me accept that you are not in charge of everything. When you were travelling with very little money, if the bus didn't come or you couldn't get a lift somewhere you just had to sort of accept things and not get into a total state about it. I think that has helped through the whole of life, you just have to sit back and wait and see what's going to happen.”

Few would begrudge the charming Harriet Graham her fairytale moment this afternoon: you know the one in which the erstwhile hippy, who trains as a hobby and was run over by her own horse box at the start of the season, saddles a Scottish National winner? Aye, right, very good.