An alteration to the programming for the South Australian Derby has forced the Mick Price and Michael Kent Jr stable into a change of planning with their trio of runners.

Price and Kent Jr won the Group 1 South Australian Derby over 2500m at Morphettville two years ago with Jungle Magnate using the Chairman's Stakes (2000m) as their lead-up run.

That race was run two weeks before the Derby and it enabled Jungle Magnate to travel back to their stable to prepare for the bigger assignment.

For this year's Derby to be run on Saturday, Price and Kent Jnr will be represented by Warmonger, Shinjuku and Tulsa King.

All three also contested the Chairman's Stakes, which was run at Morphettville last Saturday, and required the trio to remain in Adelaide at the stables of Chris Bieg.

Price said it was not ideal the way the programming worked, but he said all three geldings were in good order for Saturday's race.

"They had a trip to the beach on Wednesday and they're all bright and bouncy," Price said.

"They've all been set for it, but it's come up a much harder race than what we thought.

"The fillies are backing up into it and it's not a bad race. The St Leger winner Ahuriri is there, that's usually good form when they drop back from that race, Coco Sun and Jamie Kah, they look like the trip will be OK.

"I suppose Bold Soul might improve a bit and you've got an Australian Derby placegetter, Glad You Think So, in there as well.

"But our horses are all fit and well and I'm sure they'll run at their best."

Price considers Warmonger the best of the trio and took the blinkers off the gelding after his fifth placed finish last week.

The trainer was hoping for a mid-range drew.

"But we got 14, or 12 if the emergencies don't get a start," Price said.

"I didn't want him pulling when they slacken off the speed, especially at the 2500 metres, so I was hoping it might enable him to jump a bit better and be a bit closer.

"I'm not sure what to do with Tulsa King (from 17).

"After his last start, I was hoping to draw a gate and go forward on him, but he's there to run well.

"Shinju is one-paced. Hopefully he sticks the trip and gets a good run from the gate (two)."