Ben Melham is the new rider for South Australian-trained galloper Dalasan when the three-year-old continues his autumn campaign.

Melham replaces Craig Williams on the Leon Macdonald and Andrew Gluyas-trained colt following a first-up third as a short-priced favourite behind Super Seth in the Manfred Stakes (1200m) at Caulfield last Saturday.

Macdonald said Williams was not sacked from Dalasan having only been booked for the one run at Caulfield.

Williams has not gelled with Dalasan, a winner of five of his nine starts, having ridden the colt twice, the first time finishing second in the VRC Sires' Produce Stakes at Flemington last March.

Apprentice Raquel Clark has ridden Dalasan to four of those victories with Hugh Bowman partnering the colt in the Caulfield Guineas, when fifth to Super Seth, before his win in the Carbine Club Stakes at Flemington last spring.

Macdonald was critical of Williams' ride last Saturday where Dalasan was allowed to give too big a start before producing the quickest final 600m of the race.

"I like Ben's style and he was persistent in trying to get on the horse in the spring when he knew Raquel wasn't riding him," Macdonald said.

"There was a day when he rang me and spoke for half an hour about him.

"As far as Ben has gone about his business he has not gone out and back-stabbed anybody, so we'll see how it works out, but he's got a pretty hard assignment at his next run to beat Alligator Blood."

The CS Hayes Stakes (1400m) on February 15 is set to attract a strong field of three-year-olds including New Zealand's Catalyst in the lead up to the Australian Guineas (1600m) two weeks later.

Macdonald said Clark was recovering slowly from a head injury suffered in a fall post-race at Morphettville in November.

"She was back last week and still suffers from a few headaches," Macdonald said.

"I'm sure she has improved since I last saw her which was a month ago, but she's still got a way to go.

"Hopefully a Group One by Dalasan will help her."