The thought instantly restores his default setting, open and humorous. “Yes,” Donald McCain laughs. “Dad would have had a very good way of dealing with the whole thing. But I don’t know if I’m allowed that…”

If a hint of deprecation enters his tone, it is plainly reserved not for his late father, incorrigible as he was, but for his own circumspection. At some level, no doubt, McCain feels an ancestral urge to unburden himself of a few withering home truths, undiluted by considerations of diplomacy.

Nor can any such instinct lurk too far below a surface that so strongly evokes the old man: the big, candid features, the broad shoulders, an eye that fades from twinkling levity into a challenging hardness only when detecting some countervailing want of sincerity or trust. But here he is, trying to find the right word, the right key, precariously compromising between irreconcilables: between the ease of his nature, and the difficulty of his situation; between the need to defend himself from damaging assumptions, and a still greater imperative to move on.

It is an apt setting to catch up with a trainer urgently intent on a fresh start. McCain is taking a lunch break at the Tattersalls Horses-in-Training Sale, combing the catalogue for recruits to shore up the gaping breach created by the departure from his Cheshire stables, a couple of weeks previously, of some 60 horses owned by Paul and Clare Rooney. Their abrupt exit leaves him with only around 80, an uncomfortable number of which remain too immature to relieve his sudden exposure. Yet McCain is sticking scrupulously to the stance that neither he nor the Rooneys have anything to gain from recrimination.

We’ve still plenty of horses, but a lot of them are youngsters replacing horses that were ready to run. And too many of them are my own

His former patrons, after all, have been no less respectful in their own response to public curiosity about a mortifying failure of private chemistry. Whatever the substance of their mutual grievances, neither McCain nor the Rooneys are amplifying them beyond the formula that a virus in the stable, last season, made it seem prudent to spread risks across several different yards. That hardly accounts for the fact that McCain’s will not be among them, of course. But nor is it difficult to see why the Rooneys might conclude that retaining just a handful at Cholmondeley would place a continued relationship under intolerable strain.

In the event, they opted for a clean break. And, to their credit, neither side has indulged in bitter insinuations since. Even now, McCain refers to his departed patrons as essentially “nice people.” In fact, the only external measure of some volatility within a triangular relationship is the likelihood that Jason Maguire, on his return from injury, will still be retained in the Rooney silks – and no longer serving as stable jockey to McCain.

Kruzhlinin was one of the horses Paul and Clare Rooney removed from the McCain stable

Be that as it may, the one resentment McCain is prepared to air concerns the timing of the divorce. “If it had happened in summer, we’d have had more of a chance,” he reasons. “We’ve still plenty of horses, but a lot of them are youngsters replacing horses that were ready to run. And too many of them, at the moment, are my own. But if it keeps our people in work, in the short term, so be it. Because we’ve managed to get a great bunch together. There were a handful we did have to let go, but luckily we were a bit short-handed when it happened so we’ve managed to keep all the main staff on.

“We’re behind the eight ball, that’s clear. We spent a lot of money over the summer, laying down a deep silicone sand oval – basically to accommodate the numbers we had. I’m not going to be churning out 150 winners this season, that’s for sure. But we’re going to do the best we can with what we’ve got.”

Not that the rupture, when it came, was exactly out of the blue. Fissures of tension had evidently been spreading for a while, so much so that McCain felt something akin to relief when they all suddenly crumbled together. True, he did not find it in his heart to supervise the loading of all the lorries. For the couple of days it took to complete the job, McCain tried to keep himself out of the way. If the Rooneys had too many eggs in one basket, then so, demonstrably, did McCain himself. But could any trainer have sensibly turned down such an opportunity? The money the Rooneys were prepared to spend had the potential to take the stable to another level.

As it is, at 45, McCain finds it difficult to resist a nagging taint of humiliation – for all that the solidarity of his professional community has proved an unsuspected silver lining. Luca Cumani, his first boss when sent down to Newmarket as a 16-year-old, has himself just endured a similar calamity in the defection of Sheikh Obaid Al Maktoum. As soon as he saw his former protégé at Tattersalls, Cumani took his hand and exclaimed: “Brothers in arms!”

Look, I know I was in a very lucky position, so it’s no disaster. We’re still better off now than we have been

“To be honest, I feel a little embarrassed about how nice everyone has been,” McCain admits. “I’ve had other trainers coming up to me at the races and hugging me. But it’s nice to know you’ve still got plenty of friends. I rang round my owners the next day and everyone was wonderful. Some of my longest serving owners have sent me more horses already; one who’d left the yard during the summer sent an email the same day, promising to send me one again.

“Look, I know I was in a very lucky position, so it’s no disaster. We’re still better off now than we have been. I’ve got some fantastic owners, some very nice horses. It’s nowhere I’ve not been, it’s not strange territory. Everyone has said the same thing to me: ‘You’ve done it before, you’ll do it again’.”

It is easy, after all, to forget quite what it took for “Ginger McCain’s son” to turn the trainer of Red Rum into “Donald McCain’s father.” He was literally heir to a legend, to a Ginger who didn’t really exist outside caricature, this cheerfully outrageous taxi driver who had freakishly matched the peculiar needs of another one-off in Red Rum. Nothing pleased McCain more, in so swiftly establishing his ability to train top-class horses like Overturn and Peddlers Cross, than correcting all this folksy condescension about his father.

By the time Ginger pulled Amberleigh House out of his hat, to win a fourth National in 2004, his son was heavily involved in the yard. But when McCain saddled Ballabriggs to win the race in his own name, in 2011, it was hard to say which gave him more satisfaction: Ginger’s glow of pride, or the new respect McCain was consolidating for Ginger himself.

Just in time, too. When the old man died, only five months later, he could be mourned as flesh and blood rather than as a mere cartoon. In becoming his own man, it was almost as though McCain had rescued his father’s identity, as well. He had made people see Ginger with fresh eyes, both as a father – a man hard but fair, who taught you never to mind a rollicking so long as your honesty was never called in doubt – and as a horseman.

I stand by it that Dad could train with the best of them, but he never really got the chance

“Of course I never realised at the time that he wouldn’t be around, so soon afterwards,” McCain says. “But it does mean a lot to me now that he was there to see it. I stand by it that Dad could train with the best of them, but he never really got the chance.

“Good horses are easy to train. We’d always had to buy cheap horses and hoped to live with their problems, as things you could manage. It would bother me and my sister, the way people talked about him. He would just say: ‘Bollocks to them.’ Deep down, though, I think it would annoy him. He’d sit there listening to people on the telly, talking in clichés, and ask why they didn’t say what they really thought, why they never said anything interesting.

The McCains with 2011 Grand National hero Ballabriggs

“Of course a lot of what he did say was tongue-in-cheek. Yes, he could shout and bawl but it would all be forgotten five minutes later. Dad would be the fairest, straightest man, and the most loyal, that I ever knew. And I think Amberleigh House, in particular, proved a point. Dad had maybe six winners that season. But here was this one horse in the yard capable of running well in this one race. He’d found him, he trained him – and the horse couldn’t have gone there in better shape.

“That’s still probably my greatest day in racing, for everything that’s happened since. I’ll never forget coming back through Goodison, in the box with all the stickers on the side, and the taxi drivers calling out… we could have driven round for hours.”

But if McCain inherited a deeper grain of genius than had been recognised, he has also required something of the tough hide that had more obviously sustained the old man – not just in the present crisis, but also in the one that has turned out to be its prelude. In some ways, indeed, the virus that petrified McCain’s stable last winter was perhaps harder to take: it was more insidious, more corrosive. It lacked the vivid, dramatic quality that has caused him to be embraced by his peers this autumn, and instead left him brooding and bereft.

“I’m a true northerner,” he says wryly. “The tendency is to put your head in the sand and drive on, and I’ve always managed to work on through things. Then I took this rock-solid horse to Uttoxeter. I knew he was no flash in the pan. It was his first run for me, and he was very switched off in the paddock. I didn’t know that wasn’t his way, until we ran him three months later and he was bouncing around. What made it worse was that it was one for Tim Leslie, who has been an absolute star for us. I was stood watching with one of his sons. I’ll never forget it, I couldn’t get out of there quick enough.”

Even as the horse tailed off, McCain decided to suspend operations while he tried to get to the bottom of the problem. It was an excruciating month. Four consecutive centuries had maintained a curve of relentless progress: twice leaving him behind only Nicholls and Henderson in the prize-money table, and then twice exalting him as the most prolific trainer in the land. However lonely he felt, he soon found that he was not alone: other trainers discreetly asked to compare blood tests as they sought to end less conspicuous droughts of their own. It was no mean feat, in the circumstances, to muster 98 winners by the end of the season – albeit the plunge from the 142 of the previous campaign stimulated conclusions of staggering ignorance and malice on social media, forums and elsewhere.

“I’m not saying we’ll never get sick horses again, but it won’t be for want of trying to do things different or better,” McCain reflects. “No one thing showed up, it rarely does, but there was a pattern and I firmly believe it was connected to the very warm autumn we had. Had it happened mid-season it might have been different. But it came on just when I was starting off our winter horses. And because they weren’t finishing their races, your natural reaction is to be a bit harder on them.”

I probably worry more than I should. A winner tends to be a relief, not a joy. Quite sad, isn’t it?

Despite everything, only JP McManus and Bloomfields had more winners than the Rooneys last season. McCain does not pretend that he will relish the fulfilment, in other hands, of horses he found for them himself, and nursed through their bumpers and novices. Yet he has also resolved to maintain a better perspective than he managed last winter, when he grants that he was not always terribly easy to live with.

“Where we are now?” he says. “Dad had it a lot tougher. But he would never let himself get as upset, for instance by horses running badly. He had a great coping mechanism, because he had a life before horses. I’m not laid-back. I probably worry more than I should. A winner tends to be a relief, not a joy. Quite sad, isn’t it? I don’t particularly enjoying watching them. I do worry, I do get wound up. I don’t want to let people down when they have put their faith in you.

“I must say I didn’t necessarily want to get as big as I did. Obviously that’s not an issue now! But while I’m going to have to watch a lot of very nice horses that I bought, winning good races, it does feel a bit like a new lease. It sounds wet, but the whole thing was bothering me that much that I’m not sure it bothers me any more. Literally the day the horses left I felt better about myself again.”

Perhaps, after regrouping, big winners will have a new sweetness? Surely now, if ever, is the time to recall the old axiom: ‘Don’t get mad, get even.’ But McCain shakes his head. “It’s not about getting even,” he says emphatically. “It’s about appreciating what we’ve got. The people you’re dealing with on a daily basis, people who stick with you through thick and thin.

“To be honest, one of the biggest things I have to learn from all this is that I’ve got a nice way of life, a great family and some fantastic owners. Not to worry about what you could have, but about what you’ve got – and to enjoy it all a bit more.”