The talented but sometimes wayward Dalasan has stamped his credentials for the South Australian Derby with victory in the Chairman's Stakes.

After winning the Port Adelaide Guineas (1800m) at his first start beyond 1600m, Dalasan stepped up to 2035m for Saturday's Group Three feature at Morphettville.

Trained locally by Leon Macdonald and Andrew Gluyas, the colt was the $1.50 favourite and worked into the race at the top of the straight.

The colt has a habit of hanging in but has won seven of 14 starts, nine of which have been in Melbourne.

Jason Holder steered him to the lead and he cruised to the line 1-1/4 lengths ahead of The Moonlight Gambler ($15) with Victoria Derby winner Warning ($6) working home for third another three-quarters of a length away.

"He looked good in the run," Macdonald said.

"He did have to chase the leader but it was pretty comfortable in the end.

"He stayed very well today and he's very fit so he will have a few easy days.

"He's been very good and very happy since he came back from Melbourne."

Dalasan and Warning are among the favourites for the SA Derby on May 9 with doubts over market leader Russian Camelot who was scratched from Flemington on Saturday with a throat issue.

The other Morphettville features went to Ecumenical in the Breeders' Stakes, Wild Vixen in the Nitschke Stakes and A Shin Rook in the City Of Adelaide Handicap.