Trainer Danny O'Brien says exciting colt Russian Camelot could not be better going into the Group One South Australian Derby and is adamant missing a planned lead-up race will be no excuse.

The 2500m-Classic for three-year-olds will be Russian Camelot's biggest test but it has been a long-range target for the colt who is northern hemisphere-bred and six months younger than his rivals on Saturday.

Russian Camelot has two wins from four starts and jumps sharply in distance from winning a benchmark race at Pakenham by seven lengths over 1600m a month ago.

O'Brien scratched Russian Camelot from a 1700m-race at Flemington last Saturday week because of an inflamed throat and instead directed him to the Derby, giving him a solid 1600m jump-out.

"He couldn't be better," O'Brien said.

"He had a searching trial on Friday on the course proper at Flemington which just rounded out his preparation for the Derby.

"We're very, very happy with him.

"He just had a bit of a sore throat but he was over that by early last week and he had the strong gallop on Friday.

"So no excuses."

A field of 14 has been declared for the Derby with in-form local colt Dalasan $2.80 favourite after the barrier draw.

Victoria Derby winner Warning and Russian Camelot were both at $4.

"It's uncharted territory for a northern hemisphere three-year-old to run in a Derby down here but we've had this South Australian Derby in mind for him at least since Oaks day last spring," O'Brien said.

"Whether or not he can win it, we're all going to find out on Saturday.

"He's got to tackle two of our better three-year-olds for the season in Dalasan and Warning, so it's a very, very strong test for him.

"They are far more seasoned than him and obviously they're also six months older than him so we're well aware of the task we're asking him to do and we're not expecting it to be any pushover at all.

"We just hope he goes there and runs well."

John Allen will ride Russian Camelot for the first time with the jockey aiming for his third SA Derby after victories on Howard Be Thy Name in 2016 and Volatile Mix in 2017.

Russian Camelot has barrier seven.

"Jumping from a mile to 2500 metres we just want to make sure he switches off and relaxes, wherever that is in the race, and that will give him every chance to be strong at the finish," O'Brien said.