Love at first sight
Valegro, or "Blueberry" as he is known within the stables, turned out to be a "dream horse."
Too young to compete at a Grand Prix event, the top level of competition, Hester wanted Valegro to learn the trade under his young apprentice.
"I just fell in love with Valegro when I saw him," Dujardin said.
"He was just a powerhouse at four years old. He had paces then that he couldn't control and he had a fabulous temperament.
"He was my dream horse. And then I managed to take him out and compete him at all the young horse classes."
In their seven years together, the pair have become near inseparable, with Duajardin describing him as "my best friend and my partner."
From their first Grand Prix together in 2011, a journey which took five years in the making, the duo have not looked back.
"He always wants to please you," she said. "He goes into that arena to do his best. He never lets you down. He's with you all the way.
"To find a horse that can cope with all the atmosphere as well is very difficult. He just does it all.
"As a rider he gives you so much confidence. You go in there and you know you can do it because you know he's behind you.
"I think it was the connection we had, the fact we'd learned everything together. If I got it wrong, or if he made a mistake, between the two of us we both learned how to get it right.
"That is what was so good. He was forgiving my mistakes and I was forgiving him."
The relationship has blossomed beautifully, and they were part of the British team which won gold at the 2011 European Dressage Championship at Rotterdam.
Dujardin and Valegro then won the FEI World Cup Grand Prix at London Olympia in 2011, and set a new world points record at the Olympic Grand Prix special event the following year.
It was the prelude to the most exciting and most daunting challenge of Dujardin's career -- the London Olympics.
Competing in both the team and individual event in front of a home crowd might have left lesser riders with stage fright -- but not Dujardin.
"I see the arena, the competition arena, as an arena at home," she said.
"I do the same thing wherever I am, whether it's at home or at a competition.
"I never think of who's in the competition. I never let myself get in that frame of mind, worrying about who I'm against.
"I keep myself away, I keep myself very focused. I keep myself in that zone of what I have to do and deliver. I'm really lucky that I can control my nerves; it doesn't seem to get to me."
Just 18 months after making her Grand Prix debut, Dujardin headed out onto Greenwich Park as part of the British team seeking to win its first ever medal in dressage since 1912.
The discipline was originally used to train horses during the Renaissance period.