Docklands confirmed himself to be one of the most progressive horses in training with a third straight win in the Britannia Handicap at Royal Ascot on Thursday for Harry Eustace and Hayley Turner.

As Docklands made his move in the stands’ side group, New Endeavour was powering clear on the far side and the pair had it between them, despite being split by the width of the Ascot straight track in the final furlong.

Docklands, sent off a well-supported 6/1 favourite, edged home by half a length, winning the race on his side by a significant margin. New Endeavour (22/1) was only worn down late on and finished two-and-a-half lengths clear of Urban Sprawl (50/1), with Thunder Ball (66/1) a nose further back in fourth.

Eustace has now saddled two winners at Royal Ascot, both of which have been ridden by Turner, after Latin Lover landed last year’s Palace of Holyroodhouse Handicap.

Eustace said: “It was obviously a big performance. He hinted at his ability last time, although the ground was obviously the biggest query for everybody today, but he’s relished it. He was good and it was lovely to watch.

“I think it was more the way he went through his race last time that gave us a little bit of confidence to be able to just ride him a bit more quietly today. There would have been a natural bit of learning last time, being first time in a handicap.

“He’s always been pretty good, and we’ve always liked him, so we did come in full of confidence, although Chasing Aphrodite yesterday [last in the Royal Hunt Cup] just put me back on my haunches a little bit.

“He’ll stay a mile and a quarter in time, when we go that far. We’ll have a chat with connections, but I don’t think there’s any rush at the moment.

“Terry Henderson of OTI Racing has been a supporter of mine, and of my brother’s in Australia, from the get-go, really, and to be able to repay him with a Royal Ascot winner is very special.

“It’s always a team effort, but it’s a family business as well. Having my brother here from Oz, and my cousin, aunt and uncle - it’s very, very special. You can’t ask for more.”

Turner said: “I am so thrilled for Harry and the team. They have really come through the ranks in the last couple of years. Michael [Vockins] who looks after the horse has done a great job and he was spot on for the race.

"I thought I had my side beaten, but I knew there was one on the far side and I just had to keep my horse going forward on his own. I honestly didn't know until they called the photo whether I had won or not because the two horses were so far apart.

"It's such a thrill and today a lot of history has been made, so to look back on today is amazing."

She added: “I've had four Royal Ascot winners in recent years from about 19 or 20 rides. Someone put it on Twitter that I had a better strike-rate than the other jockeys so I re-Tweeted it and shared it – it might not last long, but I'm embracing it.

“I cannot believe it, but he [Docklands] gave me such a great ride. He's still quite lightly raced and it was a big field today. Last time it was a bit easier for him and he's still learning the ropes. I wanted cover and got him right in amongst them - when there are horses all around them and they're not used to it they can get a bit lit up, but it's another thing he'll learn from and hopefully take another step forward.

“I now need 17 for my 1,000th winner. Being part of this day has been pretty cool. I rode for Harry yesterday [Chasing Aphrodite in the Royal Hunt Cup] and we quite fancied the horse - and he finished last. Racing keeps you grounded that way - you have days like this, but also disappointments.

“My dad has just had a knee operation so will be watching from hospital, while my sister was here yesterday and made a mark - in the car park! It's quieter today, but Docklands is so popular in the yard and half of them are here.”

Roger Varian said of New Endeavour: “He ran really well and didn’t quite win. He won his side well. He’s a lovely horse."