Formlines from Sydney, Melbourne and New Zealand will converge in the Group One Randwick Guineas after 15 three-year-olds paid up for the $600,000 race at Randwick on Saturday.

Eurozone, Criterion and Teronado bring an Australian Guineas reference while Dissident and Atlante resume their rivalry after finishing one-two in the Hobartville Stakes, a traditional Guineas lead-up.

Added to the mix will be Atlante's Murray Baker-trained stablemate Show The World, one of the early fancies for the ATC Australian Derby, who will make his Australian debut having won two of his four New Zealand starts.

John O'Shea will be among those trainers flying the flag for the locals when he starts Savvy Nature, an eye-catching first-up third in the Hobartville.

The horse will have an important gear change in a 1600-metre race O'Shea concedes has great depth.

"We're going into a very strong race on Saturday so we've upped the ante with him during the week and put the blinkers back on," O'Shea said.

"It's a darn good version of the race."

O'Shea expects him to be competitive on Saturday before progressing to the Rosehill Guineas, a pivotal race which will determine if he presses onto the Derby.

The Sydney autumn will be O'Shea's final carnival as an independent trainer before he takes over the reins at Darley in May.

O'Shea is keen to mark the end of the era with a Group One success.

"It would be that little bit special," he said.

"I've got some nice chances in Group One races coming up over the carnival. Savvy Nature is one of them."

Savvy Nature has drawn gate six in the Guineas while early favourite El Roca will have to overcome a wide draw in 14 and a distance query.