The youngest horse in the field has shown stamina and staying prowess beyond his years with Russian Camelot claiming the South Australian Derby.

Bred to northern hemisphere time, Russian Camelot was giving away six months to most of his rivals in Saturday's 2500m-Classic at Morphettville.

Ridden by John Allen, the Danny O'Brien-trained Russian Camelot assumed $2.90 favouritism from Dalasan ($3.80) and punters were spot-on.

Allen brought Russian Camelot down the centre of the track to nail Dalasan and win going away by 1-3/4 lengths.

Because of coronavirus restrictions on cross-border travel, O'Brien watched the race from Caulfield.

"Obviously we're really excited. He's a horse that we've had a huge opinion of," O'Brien said.

"We've had him since he was a yearling and this was a race that we've been aiming him at for the better part of 12 months. He's turned up and delivered.

"It's very satisfying. It's never been done before - a northern hemisphere horse has never won a Derby in Australia. I don't think one has ever run?

"We were very confident going into today that there were no excuses. He'd had everything we needed to do to get him right today."

O'Brien, who won the 2019 Melbourne Cup with Vow And Declare, would not be drawn on Russian Camelot's Cup prospects but the TAB wound him into $11 favouritism.

"He's obviously been a very exciting horse, not just for us but the public as well from the time he had his first start," he said.

"We'll see about the Cup.

"He's still a young horse.

"We'll enjoy today. The owners are a great group of people who have resisted some big offers for the horse and I'm sure they're all thrilled as we are that he's won a Derby. And we'll savour that and certainly we'd be looking forward to the spring."

Despite having to complete two weeks self-isolation, Allen was lured by the quality of rides he could command, in particular Russian Camelot.

"When I got offered this ride it became a bigger carrot to head to Adelaide," Allen said.

"Danny filled me with confidence. He said ride this horse like the best horse. He was confident if he was close enough on the corner that he would have a better turn of foot.

"It proved that way. He was just the superior horse.

"Obviously he's an exceptional horse. A lot has been made about his preparation but I think the bigger factor is his still six months younger than all these horses.

"If he can beat them now and he's only just turned three, imagine what he can do in six months or a years' time."