Chris Waller continues to break records in the post-Winx era, becoming the first trainer to win four Group One races across two states in a single afternoon.

The champion horseman made a clean sweep of the three Group One races at Randwick winning the Flight Stakes (1600m) with Funstar, Epsom Handicap (1600m) with Kolding and the Metropolitan Handicap (2400m) with former Perth horse Come Play With Me.

He rounded out his collection at Flemington where Kings Will Dream held off stablemate Finche in the Group One Turnbull Stakes (2000m).

To add icing to the cake, Waller saddled up runners in six of the nine races at Randwick on Saturday and won them all.

Waller's Group One feat has never been achieved by an Australian trainer, the previous best being David Hayes who prepared three Group One winners at Flemington on Derby day in 1990 and six Group winners on the card.

"It's been a very special day and a massive team effort," Waller said.

"We've got a great team and that's what a great team does."

Come Play With Me's Metropolitan win gave Waller the full suite of Group One races on Saturday and had added significance given the horse was sent to him by successful Perth trainer Adam Durrant.

Durrant felt the horse had reached his mark in Perth and hoped Waller might find a race or two in Sydney.

"From memory he just rang up and said, 'I've got a horse I want to send over to you, he's going well, he's been weighted out of it in Perth, we're not expecting anything great but just run him in races you think are right'," Waller said.

"That's what we've done and I've given Adam a bit of confidence to say this is the race to target.

"He's probably still standing there with his mouth open but I got it right Adam."

Come Play With Me had late specking to start $8.50 and downed Gallic Chieftan ($18) by a long head with Sir Charles Road ($31) sticking on well another long neck back.

The victory was also momentous for Brenton Avdulla who has now won all three Group One races on the Epsom Handicap program.

"This day has always been a big day for me, I've won all three Group Ones now, the Flight, the Epsom and now the Metropolitan," Avdulla said.

"I thought this was the horse I wanted to ride with the weights, I was very lucky to have Chris (Waller) put me on him."

Waller said he didn't come to Randwick with any expectations and was thrilled he could continue to raise the bar, even without Winx.

"I still doubt myself and check myself and make sure we're not getting ahead of ourselves," Waller said.

"But I think once you get complacent in any sport you can soon drift off the pace and we dare not let that happen."