Trainer Adam Trinder has confirmed Mystic Journey will press on to the $5 million Cox Plate at The Valley after her fifth placing in the Turnbull Stakes.

Mystic Journey was tested over 2000m for the first time in Saturday's Turnbull at Flemington and came from back in the field to finish fifth in the race won by Kings Will Dream.

Third acceptances for the Cox Plate are due on Tuesday and Trinder has confirmed the Australian Guineas and All-Star Mile winner will run in 2040m weight-for-age showpiece at The Valley on October 26.

"Mystic Journey has pulled up in fantastic order from Saturday's run and the decision has been made to proceed to the @CoxPlate," Trinder said.

Te Akau Racing has also confirmed Epsom Handicap runner-up Te Akau Shark will take his place in the Cox Plate.

Mystic Journey won the P B Lawrence Stakes (1400m) first-up this preparation before running second in the Group One Makybe Diva Stakes (1600m) and fifth in the Turnbull.

After the Turnbull on Saturday, Trinder said he felt the mare ran great but the race did not pan out for her.

"She was back, cluttered through the entrance to the straight but I thought she hit the line with really good enthusiasm," Trinder said.

"I still think we're full of confidence with her. We thought that she really ran the 2000-metres and she kept galloping right through the line."

Mystic Journey is currently at $7 for the Cox Plate behind Avilius, who has his next start in Saturday's Caulfield Stakes, and Japanese mare Lys Gracieux who are both at $5.