A decision on a Melbourne Cup start for English raider Yellowstone is likely to be delayed until at least Wednesday.Yellowstone had treatment from an equine physiotherapist after injuring a hip in his box on Monday.Trainer Jane Chapple-Hyam said the horse had improved by the hour on Tuesday, but until the extent of the injury could be determined she would be unable to confirm Yellowstone as a starter.The accident came a day after Chapple-Hyam talked up the horse's prospects, claiming the 50-1 ch

A decision on a Melbourne Cup start for English raider Yellowstone is likely to be delayed until at least Wednesday.

Yellowstone had treatment from an equine physiotherapist after injuring a hip in his box on Monday.

Trainer Jane Chapple-Hyam said the horse had improved by the hour on Tuesday, but until the extent of the injury could be determined she would be unable to confirm Yellowstone as a starter.

The accident came a day after Chapple-Hyam talked up the horse's prospects, claiming the 50-1 chance had the form to match it with Caulfield Cup winner All The Good.

The trainer said Yellowstone appeared to have got down in his box after working on Monday.

"He loves to roll," Chapple-Hyam said.

"It looks like he's had a roll in his box and got stuck, you can see the scratches all over the walls where he's thrashed about."

It is believed the horse hurt himself as he struggled to his feet.

The physiotherapist is scheduled to treat the horse again on Wednesday with his only exercise likely to be confined to walking.

Yellowstone's prospects of getting to the start will depend largely on the exact location of the injury and what treatment is available to him.

Chapple-Hyam acknowledged that with the Cup only a week away, it was impossible to give the horse a course of anti-inflammatories which would have to be out of his system by race day.