Gai Waterhouse could have four runners in her bid for a sixth Golden Slipper with Speak Fondly adding her name to the team with her win in the Magic Night Stakes.

The trainer already has the favourite Vancouver and fillies English and Flamboyant Lass heading to the $3.5 million race next Saturday.

She will discuss the Slipper with Monica Barrera, the racing manager for her grandfather Eduardo Cojuangco's Goree which races the filly.

"I don't know yet whether she will run," Waterhouse said.

"I'll ask Monica and see if she wants to start her next week.

"She has got spring form. She was third in the Gimcrack and is now the winner of the Group Two today."

Tommy Berry, who rode Speak Fondly on Saturday, is already committed to Vancouver who is at $2.80 in the Slipper.

Speak Fondly ($4.60) led all the way to beat Perignon ($9) who failed by just a half head to catch the winner.

Although she would gain a Slipper start, Perignon will be saved for the Sires' Produce Stakes a week later.

That is also the case for Godolphin's Tarquin, winner of the Pago Pago Stakes for colts and geldings.

Tarquin ($14), who gave visiting England-based jockey William Buick his first Australian win, came out of the pack in the straight to beat Rageese ($13) and Odyssey Moon ($4.40) with favourite Inner Circle ($3.60) fourth.

"We thought Inner Circle might have been a bit good for him," trainer John O'Shea said.

"I think Tarquin's got a very, very bright future. Going forward into the Sires Produce and the Champagne he'll be quite effective.

"We didn't expect him to win a race like this and we have a good representation in the Slipper.

"We been looking at the other races for him since he came to the stable."

The field and barrier draw for the Slipper will be finalised on Tuesday morning.