Between them, Gai Waterhouse and John O'Shea will be responsible for half the Golden Slipper field while rival trainer Gerald Ryan is banking on his lone runner to cause an upset.

Fireworks' owner John Camilleri will pay the $150,000 late entry on Monday to put the filly in the $3.5 million race.

She is a $26 chance ahead of the declaration of the final field for Saturday's feature with the Waterhouse-trained Vancouver leading her quartet at $2.80 ahead of Godolphin's O'Shea-trained Exosphere at $4.60.

The Slipper was far from Ryan's sights when Fireworks entered his stable in September but she has earned her way with her Widden Stakes win on January 31 and her third behind the Waterhouse-trained English in the Reisling Stakes.

"As long as she works well on Monday morning, John will pay up," Ryan said.

"I know she can match it with the fillies and her last run has brought her on a lot."

Fireworks' sire Snitzel, trained by Ryan, was the unplaced favourite in the 2005 Slipper. His daughter Snitzerland, also trained by Ryan, finished second to the Waterhouse-trained Pierro three years ago.

Waterhouse will be aiming for her sixth win in the race with Speak Fondly adding her name to the contenders with her win in Saturday's Magic Night Stakes.

Damien Oliver will ride the filly who joins stablemates Vancouver, English and Flamboyant Lass.

Godolphin won the last of the qualifying races for colts and geldings, the Pago Pago Stakes, with Tarquin but he will be saved for the Sires' Produce Stakes on April 4, a week after the Slipper.

O'Shea's best Slipper finish as a public trainer was with Charge Forward who ran second in 2004 to the Waterhouse-trained Dance Hero.

He saddles up Exosphere, Furnaces, Haptic and Ottoman in his new role as Sheikh Mohammed's No.1 trainer in Australia.

David Hayes has confirmed he will have two runners, Blue Diamond runner-up Reemah and Haybah.

Ryan said Perignon, second to Speak Fondly in the Magic Night, would be saved for the Sires' Produce which he won last year with Peggy Jean.

"Peggy Jean ran second in the Magic Night and then came out and won the Sires' so I'm taking that as an omen," he said.