With Royal Ascot almost upon us and Aidan O’Brien on the cusp of sending out his 400th Group One winner on the Flat, his sons have hailed their father’s “sheer dedication” to his craft.

Both Joseph and Donnacha O’Brien have had the privilege of growing up at the heart of their father’s Ballydoyle operation, witnessing first-hand the hard work and sacrifice that creates a champion team of horses.

The two brothers have followed their father into the training ranks and are both winners at the highest level in their own right.

However, 28 years after O’Brien’s first top-level success the big-race winners continue to fly off the Ballydoyle production line of champions, as the Tipperary handler seeks to reach the accolade of 400 winners at the top table.

“He’s been incredible season after season for a number of years and his sheer dedication to the task and will to win races really is extraordinary,” said Joseph O’Brien.

“I was blessed to have grown up in the environment that is Ballydoyle, it really is a special place to grow up.”

Donnacha O’Brien was not even born in 1996 when his father registered his first Group One success with Desert King in the National Stakes.

Watching success at close quarters has been commonplace for the youngest of O’Brien’s four children as a stocked trophy cabinet became literally part of the furniture at home.

And since becoming a trainer in his own right, he has come to appreciate just what separates his father from the rest.

“It’s incredible really and he trains to a level of detail much higher than anyone else I’ve seen,” he said.

“It’s something I have tried to replicate, but can’t really get close to and I don’t think anyone else can either from what I have seen in all other training establishments.

“It’s not a surprise (getting to the landmark) and when you are in Ballydoyle and see the way things are done there, and then when you combine that with the horses he gets, it’s no surprise the results he gets.”

The 25-year-old also admitted he often wishes he could temporarily revisit his youth and return to Ballydoyle to bottle just a touch of his father’s genius.

He went on: “I suppose it was normal for us growing up and then it’s only when you step away you start to appreciate just what he is doing. When you try to replicate it, that is when you realise how hard it is.

“When I was growing up, it was kind of the norm, but I’ve discussed this with Joseph and we kind of say we would love to go back to Ballydoyle for five years now and you would nearly learn more than what you did at the start because you understand a bit more about training them. It’s just incredible the way he does things.”

O’Brien has been churning out top-level winners for more than a quarter of a century and not only did the brothers get to wonder at his training talents as wide-eyed youngsters, they also got to experience his influence when donning the famous silks of the Coolmore partners in the saddle.

Both would become a part of his historic 400 Group One winners and enjoyed Classic success while riding for the master of Ballydoyle, with O’Brien and Joseph becoming the first father-son/trainer-jockey combination to win the Derby when Camelot was victorious at Epsom in 2012.

The three-time Classic winner – who came within three-quarters of a length of landing the Triple Crown – was signalled out alongside the mighty St Nicholas Abbey when Joseph was asked to pick out some of his personal favourites from his father’s quadruple century.

He said: “Two that will always stick out to me is Camelot winning the Derby and St Nicholas Abbey at the Breeders’ Cup. They were both incredibly special horses and we had some special days.”

After his brother hung up his saddle in 2016, Donnacha played his part alongside Ballydoyle number one Ryan Moore and enjoyed his fair share of big-race victories for his father.

A pressurised position riding Classic contenders already earmarked for the breeding sheds, he admits he understood the weight of expectation on his shoulders, but is grateful to have had such precious opportunities during his father’s record-breaking training career.

He said: “I had some great days on some very good horses. I was lucky enough that any time Ryan Moore wasn’t available or was abroad, I was able to step in on some of them and try not to mess up.

“I suppose Saxon Warrior was the first one of my big rides for dad so he is kind of one who stands out, but there were plenty of great days and I was very lucky to ride his horses.

“There was always pressure, but it was never put on you by dad or the owners, they were very easy to ride for, and so was dad.

“It was probably me putting pressure on myself more than anything because you know what is at stake and some of the colts would have a stallion career ahead of them and it was important to get it right.

“So I probably always did feel the pressure, but that was more put on by myself as I didn’t want to let anyone down.”