Jockey Craig Newitt believes Tarzino can give him his biggest win this spring and bookmakers agree with the Victoria Derby winner retaining favouritism for the Caulfield Cup after the release of weights.

Newitt is the regular rider of the Mick Price-trained Tarzino and has combined with the trainer to win 18 Group One races, although neither has won one of Melbourne's three biggest races - the Melbourne Cup, Caulfield Cup or Cox Plate.

"I think if we're going to win a Cup it will be with this horse," Newitt said.

"He's got Cups written all over him. We've just got to get him there in one piece I think and he'll be very competitive."

Tarzino was given 54kg when Caulfield Cup weights were announced on Wednesday and is the $13 favourite with the TAB.

Melbourne Cup favourite Order Of St George has been given equal top weight of 58kg for the Caulfield Cup but the Aidan O'Brien-trained horse, who is part-owned by Lloyd Williams, is unlikely to travel to Australia.

His stablemate Highland Reel is the other topweight.

Melbourne Cup winner Prince Of Penzance and Australian Cup winner Preferment are next in the handicaps with 56.5kg while French horse Erupt and last year's Caulfield Cup placegetter Our Ivanhowe have 56kg.

Tarzino and Australian Derby winner Tavago are the highest-weighted four-year-olds on 54kg, with Tarzino out to become just the fourth horse and first since Elvstroem in 2004 to win the Caulfield Cup a year after winning the Victoria Derby.

"That's what we thought he would get," Newitt said.

Tavago will be striving to become the second-straight Australian Derby winner to win the Caulfield Cup after Mongolian Khan last year.

VRC Oaks winner Jameka has 51.5kg while Godolphin-owned Scottish, trained by Charlie Appleby at Newmarket in England, has 54.5kg.

Highland Reel, Jameka and Scottish share the second line of betting at $18.

Williams' son Nick said on Twitter that Order Of St George was unlikely to travel to Australia.

"Proves weight not only stops trains, but planes as well!" Williams tweeted.

Last year's Cox Plate placegetter Highland Reel is the highest-rated among the 171 Caulfield Cup nominations.

Highland Reel won the Hong Kong Vase last year and the Group One King George VI (2012m) in England earlier this year to earn his equal topweight.

Dunaden (2012) and Admire Rakti (2014) are recent internationally-trained horses to carry top weight to win the Caulfield Cup.

Melbourne Cup weights are released on September 13.