Trainer John O'Shea has confirmed course specialist Kencella for a seven-day back-up in the $400,000 Galaxy at Rosehill.

In a move that might have seemed far-fetched a week ago, Kencella will take his place in the Group One sprint on the 52kg limit.

O'Shea said a decision to start Kencella for the second time in seven days was more about timing rather than any long-term plan.

"The horse has virtually pushed me towards running him in the race," O'Shea said.

Kencella made it three wins from as many 1100m Rosehill starts with his Maurice McCarten Stakes victory over Va Pensiero last Saturday.

"He's done very well since, he loves the track and he's won in the wet so why not give him his chance," O'Shea said.

"I've always had a really good opinion of him.

"And there's not too many times you can get a horse into a Group One race with his weight in his sort of form."

Kencella will go into the Galaxy as the winner of his past three starts after making a transition from benchmark racing to stakes grade last week.

O'Shea is counting on improvement on the training track - and not the Randwick Guineas result - as the best guide to Savvy Nature's chances in the Rosehill Guineas.

Savvy Nature finished seventh at Randwick, leaving O'Shea wanting something a bit better than a midfield finish to Dissident.

"I thought he ran an even race although I would have liked to have seen him finish a length or so closer," O'Shea said.

"But his work was much better this morning."

Although Randwick-trained, O'Shea said Savvy Nature had run his best races away from his home track.

"For some reason he seems to go better at Rosehill than he does here," he said.

Nominal Guineas favourite Dissident worked with Epona Stakes entry Sensibility on the course proper on Tuesday morning.

They were sent over a leisurely 1600m on a track rated just into the slow range in 1min58.55secs but their 11.3secs for the last 200m was up there with the best of the session.