In a spring already plagued by casualties, Mosheen is both a victim and a survivor.

The VRC Oaks winner of last spring and triple Group One winner in the autumn, Mosheen's Cox Plate preparation was well underway when a breathing problem emerged.

A relatively straightforward piece of surgery and a week or so recuperating fixed things and Mosheen eventually resumed with a slightly-concerning 13th at Flemington.

The run put a new perspective on Mosheen's preparation and trainer Robert Smerdon expects a better showing form Mosheen at Caulfield on Saturday.

"The day she had the surgery she was due to trial over 1200 metres," Smerdon said.

"Then we gave her a quiet week after that and then started doing a bit more, but you're really not back to where you left off.

"So there was probably a bigger hole in the middle of her preparation than I first thought."

Mosheen runs in a heat of the Group Three Sportingbet Sprint Series (1200m) and Smerdon expects her to be competitive.

"She's going well but we've got quite a bit of ground to make up .... she needs some match practice," he said.

The catching up process gets serious after Saturday's run with only an eight-day break planned before her next start in the Group One Sir Rupert Clarke Stakes (1400m) at Caulfield on Sunday week.

Smerdon also has a strong hand on Saturday in the Group Three Thousand Guineas Prelude (1400m) with last-start winners Members Joy and Bloomingdale Miss.

The trainer said Members Joy had worked sharply at Caulfield on Tuesday and was expected to run up to her best form.

Bloomingdale Miss is likely to need some give in the ground to encourage her to produce her best.

Both fillies are on track for the Group One Thousand Guineas (1600m) at Caulfield on October 17.