Robert Smerdon says the early stages of Saturday's Tristarc Stakes will be crucial for star mare Mosheen, who the trainer believes is getting close to her peak form.

Mosheen's spring carnival had to be altered early in the campaign after she had to have surgery to repair a throat issue.

After two unplaced runs, the multiple Group One winner then bounced back in the Group Two Blazer Stakes (1410m) last start at Flemington.

The Group Two Tristarc (1400m) at Caulfield will be the mare's final lead-in to the Group One Myer Classic (1600m) in two weeks, the race which replaces the Cox Plate as her main spring aim following the early-campaign setback.

"She has got back to full fitness and she's in good order," Smerdon said.

The trainer said the mare could be looking for further than the 1400m but believes the distance won't be the favourite's biggest hurdle.

"I think she's OK there (at 1400m) but the biggest issue is her awkward barrier (11)," Smerdon said.

"From the 1400-metre start at Caulfield you climb a hill and it's not a good scenario to be working hard. She'll just need a bit of luck in the first 300 metres.

"If she gets over that hill and gets some cover close to the fence, I'll be more comfortable."

Smerdon said it was a "relief" to see Mosheen return to winning form last start and had continued to please since.

The Blazer victory was Mosheen's eighth win from 17 starts with her record including Group One successes in last season's VRC Oaks, Australian Guineas, Randwick Guineas and Vinery Stud Stakes.

Smerdon rates the Chris Waller-trained Red Tracer, a first-up winner in the Premiere Stakes in Sydney and second favourite for the Tristarc, as Mosheen's biggest danger.

"I just think she's got good recent form and is drawn to get a good run (from barrier three)," Smerdon said. "She ticks a few boxes."