Delicacy has headed an historic Perth Cup trifecta for Western Australia's biggest owner Bob Peters.

Last season's champion Australian filly, Delicacy carried 59kg to confirm her position at the top of WA racing in Saturday's 2400m Group Two Cup at Ascot.

The star mare beat her Grant Williams-trained stablemate Neverland with last year's Cup winner Real Love from the Adam Durrant stable third.

Leading rider William Pike opted to ride Neverland with Peter Hall guiding Delicacy along the rail to win by three-quarters of a length.

Hall was aboard when Delicacy won the Australasian Oaks and SA Derby last season.

It was a sixth Perth Cup for Peters, who also won with Field Officer (1993), Crown Prosecutor (2005), Lords Ransom (2010), Western Jewel (2012) and Real Love (2014).

"I wouldn't say it's my most memorable Perth Cup but it's right up there with Field Officer," Peters told RWWA.

"She surprised us last year and continues to surprise us this year,."

Hall admitted he was concerned when Delicacy was shuffled back.

"I was always worried but you find a way," he said.

"It's like peak hour traffic you have to get out. But I had utmost confidence in the horse.

"She is a freak."