New Zealand trainer Murray Baker is taking aim at a second Derby this autumn, albeit with a less high-profile horse than It's A Dundeel.

The South Australian Derby is the target for Serpent as long as he proves he can be a worthy contender with a good performance in Thursday's VRC St Leger (2800m) at Flemington.

Australian Derby winner It's A Dundeel returns to Randwick on Saturday for his first weight-for-age test in the Queen Elizabeth Stakes (2000m).

Serpent won the NZ St Leger in March and finished fifth at his first Australian start in the Galilee final over 2500m at Flemington last Saturday week.

"He's a one-paced stayer and I think he was in need of a run last time," Baker said.

"He won the New Zealand St Leger before he went to Australia and I'm hoping he's a bit fitter this time.

"The South Australian Derby is the plan if he measures up.

"I'd like to go to Adelaide. I haven't won a Derby there. The closest I've come was when The Phantom came second in 1989."

Galilee winner Shoreham is also headed to the SA Derby (2500m) on May 4 but will not run in the St Leger.

Gai Waterhouse has entered Hippopus and King Of Olympia in the St Leger.

Hippopus finished fifth in the Australian Derby while King Of Olympia would have to back up from his unplaced finish over 1800m at Caulfield on Saturday.

Brad Rawiller has been booked to ride Serpent providing he recovers from the illness which forced him to miss Monday's Stawell meeting.