Mark Newnham has done the research and he is convinced Nakeeta Jane deserves a shot at a feat only one other filly has managed in the past 15 years.

The Surround Stakes winner is one of three fillies backing up from last weekend's Group One race to take on their male counterparts in Saturday's Randwick Guineas.

Her presence has added some much-needed spark and Newnham is excited about the impending clash with Australia's benchmark colt and race favourite The Autumn Sun.

"You have a Randwick mile, you've got the best colt, I think I've got the best filly, so you put them in a contest with some other chances and you get a good race," Newnham said.

"For someone who enjoys racing like I do, I can't think of anything better."

Mosheen in 2012 is the only filly to have won the Guineas in its current format but after delving deeper into their record in the race, Newnham is satisfied Nakeeta Jane isn't facing an insurmountable challenge.

Only two fillies have contested the Randwick Guineas in the past three years - Invincible Gem who was runner-up to Inference two years ago and Stay With Me who was fourth behind Le Romain in 2016.

"I've had a look, don't worry," Newnham said.

"Generally the fillies don't run but the ones that do, run well.

"They haven't been tested much in the race but this year's group of fillies is exceptional and they've generally had the better of the colts when they've met, bar The Autumn Sun."

The Autumn Sun is odds-on for the Group One Randwick Guineas (1600m) with Nakeeta Jane on the second line of betting at $6.

Newnham said the filly had come through her Surround performance in great shape and all the indications pointed to her coping with her first seven-day turnaround.

"She did a little bit of work this morning, she's eaten well, she looks exactly the same as she did last week," Newnham said.

"Her blood is good and there's no reason not to run."

While Newnham only confirmed Nakeeta Jane for a Guineas start this week, he has been weighing it up for a while.

He sounded out Josh Parr about getting down to 54.5kg a few weeks ago and the jockey committed to the challenge of riding at his lightest weight for some time.

Surround Stakes runner-up Fundamentalist and the Kris Lees-trainer Miss Fabulass round out the fillies' contingent in the nine-horse Guineas field.