Jockey Anthony Darmanin is confident Mystic Journey can erase any distance doubts heading towards the $5 million Cox Plate when she returns to Flemington for the Group One Turnbull Stakes.

The Adam Trinder-trained Mystic Journey was beaten for the first time in 12 months when West Australian gelding Gatting caused a boilover in the Group One Makybe Diva Stakes at Flemington over 1600m on September 14.

Mystic Journey, who won the Australian Guineas and All-Star Mile at Flemington over 1600m during the autumn, steps to 2000m for the first time in Saturday's Turnbull.

The Cox Plate (2040m) at The Valley, the Tasmanian mare's major spring aim, is three weeks later.

"I think the 2000 won't be an issue at all," Darmanin said.

"She probably ran 2000 in the All-Star Mile, pretty much.

"I think she will be strong on the line.

"I think the month between runs last start probably took a toll. Not taking any credit away from Gatting though because he won really well and was better on the day.

"Adam said she has worked really well during the week so I'm just looking forward to Saturday."

Darmanin said he thought Mystic Journey lost no admireres when second in the Makybe Diva.

"She was just a little bit hot behind the barriers, which she is not like, and even on the way to the start she was a bit keen and usually she's so relaxed and just looking around," he said.

"She was just a little bit on her toes so I think she just wanted to get that run over and done with.

"Even though I thought she ran super, I think this Saturday she's going to be a lot better."

Mystic Journey was the $2.70 favourite on Thursday for the Turnbull which has been reduced to a field of 11 after the scratching of Verry Elleegant who runs in the Hill Stakes in Sydney.

Darmanin has ridden Mystic Journey in 14 of her 15 starts for 11 wins, including a first Group One in the Australian Guineas and the mare is the current $5 equal favourite for the Cox Plate.

"I'm still pinching myself, one horse can take you so far," Darmanin said.

"It's a journey I thought I'd never be on and I'm loving it. I'm just trying to lap it up and just block out the outside noise and just do my job.

"I'm sure she's going to put her best performance in so that's all I can ask for."