Melbourne Cup winner Protectionist will have his next start in the Group One Turnbull Stakes after a solid George Main Stakes performance.

Trainer Kris Lees confirmed the German import would head straight to Melbourne for the 2000m Flemington feature on October 4 in his next step towards a defence of his Cup title.

Protectionist finished less than six lengths from George Main winner Kermadec in Saturday's Group One race at Randwick over 1600 metres, a distance well short of his preferred range.

"He was a bit sluggish the other week but (on Saturday) he was a bit sharper," jockey Christian Reith said.

"He was out-sprinted at the top of the straight but the last bit he was good again."

Protectionist is the 58kg equal topweight with English horse Snow Sky for the Melbourne Cup and is at $21 in the TAB's early market.

Stablemate Lucia Valentina finished fourth in the same race, hitting the line strongly after coming from second last on the turn.

She has been vulnerable second-up in the past but her jockey Brenton Avdulla said the mare's run was full of merit given the slow tempo of the race.

"The speed of the race didn't suit her and we had to wait for everything else to go but she hit the line well," Avdulla said.

Lees is keeping his options open for Lucia Valentina with Group One races in Sydney and Melbourne still under consideration.

She could join Protectionist in the Turnbull Stakes, a race she won last year, or head back to Randwick in two weeks for the Epsom Handicap.

The Group One Caulfield Stakes on October 10 is also a possibility.