Blake Shinn has been booked as the replacement rider for Rosehill Guineas winner Volkstok'n'barrell who is set to make his mark in the Memsie Stakes at Caulfield.

Craig Williams rode the Donna Logan-trained gelding to his Group One autumn win in Sydney but his commitment to a jockeys' series in Japan on August 29 left the Memsie mount up for grabs.

Logan and her fellow owners had also considered running Volkstok'n'barrell in the Makfi Challenge in New Zealand on the same day but said Melbourne was the preference.

"He is 99.9 per cent running in the Memsie with Blake to ride," Logan said.

"He will go to Australia next week. He is ready to race and I couldn't be happier with him."

The Memsie and the Makfi, both over 1400 metres, are the first Group One races in Australasia for the new season.

Both Volkstok'n'barrell and Australian Derby winner Mongolian Khan are at $21 for the Cox Plate with Contributer, Criterion and Pornichet sharing the top line of betting at $11.

Volkstok'n'barrell finished second to Mongolian Khan in the New Zealand Derby and third in the Australian Derby after his Rosehill Guineas win.

The Murray Baker and Andrew Forsman-trained Mongolian Khan, fifth in the Rosehill Guineas, is the newly crowned NZ Horse of the Year and is also scheduled to cross the Tasman next week.

His first race is scheduled to be over 1600 metres in the Group One Makybe Diva Stakes on September 12.