The Danny O'Brien-trained two-year-old Prompt Return has backed up a debut win at Bendigo with victory in the Group Three Maribyrnong Plate at Flemington.

Race experience proved telling in the Maribyrnong Plate as the Danny O'Brien-trained colt Prompt Return raced to a convincing victory.

Prompt Return was one of four two-year-olds with race experience in the 14-horse field and it had been 18 years since a horse on debut had won the Group Three race for juveniles at Flemington.

Godolphin debutant Bantam was the $2.60 favourite but Prompt Return ($19) found the rail on the inside section of the straight 1000-metre course and produced an strong on-speed display to win by two lengths over Old Trieste ($21) with a half length to Sailing By ($11) in third.

Bantam, who came down the middle of the track as the field split into two divisions early, finished fifth.

Prompt Return had won his maiden on debut at Bendigo last month and connections will consider aiming him at the rich Magic Millions on the Gold Coast in January.

He is from the first of only two crops sired by young stallion Beneteau who died early last year.

Prompt Return was Beneteau's first winner at Bendigo and became his first stakes winner on Saturday.

"He's a very nice colt," O'Brien said.

"He went to Bendigo, really as a barrier trial and he won.

"He came home and improved a lot in the three weeks since then and you saw that improvement today."

Prompt Return is likely to have his next start in two weeks in the Magic Millions Clockwise Classic at Ballarat, should connections decide to target the Gold Coast race.

Jockey James Winks said the colt's natural improvement from Bendigo was incredible while O'Brien is hoping he continues to improve during his juvenile season.

"The secret of good two-year-olds is every time you take them back to the races they step up," O'Brien said.