As a renowned no-nonsense Yorkshireman, Cowen does not deal much in “ifs”. But then, he does not normally deal in “putts” either. “It’s funny, because the stats guys are saying that was one of Rory’s best-ever performances on the greens and I gave him a putting lesson before he went off to Quail Hollow,” Cowen said. “And that’s the one aspect of the game I never teach. Maybe I should branch out.”

Cowen laughed down the line from Orlando, where he is staying with Ricky Elliott, the caddie of Brooks Koepka, another of Cowen’s four-time Major-winning clients.

The 70-year-old recognises he is busy enough and that is why he was not at the Wells Fargo Championship when McIlroy prevailed by a shot over Mexican Abraham Ancer in dramatic scenes on Sunday night.

“I didn’t even see it as I was on the range with (Henrik) Stenson and had been with (Ian) Poulter earlier on in the day. I figured that not only with Rory, but also Gary Woodland (the former US Open winner who finished fifth) in the mix that we’d have a winner.

“I guess Rory isn’t used to having a coach with a few runners in the race, but that might be a good thing, as it’ll keep things a bit less intense. I had three days with him at his place the week before last and we got through a lot of stuff. But you can see from his driving stats that there’s plenty to do and that potential for improvement should fill him full of self-belief.”

McIlroy hit only 19 fairways all week, the fewest by a PGA Tour winner in 33 years. His waywardness also cost the 32-year-old on the 18th when, with a two-shot advantage, he pulled his tee shot into a wretched lie by a water hazard.

“I watched the highlights and he played some great shots under pressure down the stretch, and again, that’ll do wonders for his confidence,” Cowen said.

“That’s what I wanted him to do – forget about technique and just play and with his irons you can seen he is doing that. But his driving has had this two-way miss going on and when people are saying, ‘what has Cowen done to his beautiful draw?’ they must realise that the modern equipment will not let him do his old slinging right-to-lefter and it was him trying to do it that was forcing him all over the place.

“So, we are looking to be more neutral and if that creates a slight controllable fade then so be it. It’s a cliche, but it really is all a process.

“As it was, he and Harry (Diamond) dealt well with the situation on the last. It showed Harry’s qualities, persuading Rory to take a penalty drop from which he’d get a good lie and could go for the green, rather than risking chopping it out. A lot of rubbish has been talked about Harry being Rory’s mate and not being up to the job. But there’s an awful lot of c*** spoken about Rory.”

Cowen has coached players who have won 14 Majors and more than 300 titles between them in his near-40 years as an instructor. But when McIlroy appointed him at the end of March, entrusting somebody other than Michael Bannon with his swing for the first time since he was eight, he was taken back by the reaction.

“I’ve told him, ‘you have no idea how much pressure you are under’,” Cowen said. “I had a couple of days with him before the (WGC) Match Play and some of the TV pundits were analysing him, picking holes in what we’d supposedly been working on.

“I’d had a few sessions with him and former pros who should know better, some of whom I’ve actually coached in the past, were blurting out all this knee-jerk nonsense. Judging my work with Rory so quickly was as daft as calling me a miracle worker now.

“ That’s what I meant about intense. It’ll help him if it’s a bit more low key. But the hype over him is on the Tiger Woods level and that’s not fair as there’ll only ever be one of Tiger.”

McIlroy was seeking to end a slump that took him to world No 15, his lowest ranking in more than 11 years.

“We need to get the technique right first, because otherwise it doesn’t matter what your attitude is if you can’t hit it,” Cowen said. “We are getting there and it was nice to get a text off Rory on Sunday night saying ‘I never expected it to turnaround this quick, but I’m glad that it has.’

“Watching the tape back and hearing that US crowd chanting his name was extraordinary. Everyone wants him back to his best. He’s fantastic to watch.

“He has not won a Major in seven years, but won by eight the last time the PGA was held at Kiawah Island (in 2012). He’s just shown by winning for a third time at Quail Hollow that he can be very dangerous when he feels comfortable.” 

Telegraph Media Group Limited [2021]