Chris Waller will study the weights for this Saturday's Newmarket Handicap before deciding whether Espiona runs in the $1.5 million sprint at Flemington or returns to Sydney.
The daughter of Extreme Choice caught the eye late when steaming home into third placing in the 1000-metre Black Caviar Lightning, won by Imperatriz.
The star Kiwi mare was late last week confirmed as a Newmarket starter, where she is expected to be 58kg topweight, and Waller said how Espiona measures up against her and some of the other better-performed nominations will determine whether she takes her place in the 1200m race.
"I just want to see not what weight she gets, but how she fares in the weights against the other horses," Waller said.
Private Eye, Bella Nipotina, Magic Time and Skew Wiff are the other Group 1 winners entered for the Newmarket, along with Buenos Noches, Benedetta and the lone three-year-old nomination Cylinder.
If Waller opts against running in the Newmarket, she will most likely appear in the Group 1 Canterbury Stakes at Randwick.
The five-year-old was one of 13 nominations for that $750,000 event, which will herald the return of The Everest winner Think About It, and Waller would not have too much issue seeing her jump from the 1000m of the Lightning to 1300m second-up.
"I don't see 1300 metres being much of a problem, I think it is a good distance for her," he said.
"Her first-up run was terrific. She is effective now both ways as well as up the straight."
Espiona is one of two Canterbury Stakes nominations for Waller, who also has Golden Slipper winner Shinzo entered.
The valuable son of Snitzel has not started since his third placing in the Coolmore Stud Stakes third placing and Waller tossing up whether he is ready for the 1300m first-up.
"I've still got to make a decision if Shinzo is quite ready for it," he said.
Shinzo had had two trials this preparation, a third over 900m at Randwick on February 8 before a sixth placing in an 850m trial at Randwick a fortnight later.