Dwayne Dunn is on standby to ride Lucia Valentina if the mare takes her place in the $3 million Caulfield Cup.

Trainer Kris Lees will make a final decision on a start after Lucia Valentina gallops in Melbourne next Tuesday when acceptances for the handicap are taken.

The two-time Group One winner finished third in the Caulfield Cup 12 months ago but disappointed at her most recent start in the Epsom Handicap when she finished midfield.

Lees will have at least one Caulfield Cup runner with Protectionist a certain starter.

The horse was beaten less than four lengths by Preferment in the Turnbull Stakes on Sunday and will be ridden in the Caulfield feature by Brenton Avdulla.

Protectionist's campaign is being designed around a defence of his Melbourne Cup crown.

"We've got one race in mind with him," Lees said.

Thirty-eighty horses, including five internationals, were paid up for the Caulfield Cup when the latest declarations were taken.