The Hong Kong-based jockey won last year's Caulfield Cup on Admire Rakti but thinks Fame Game will be better suited in the Melbourne Cup.
"The horse that was here last year was probably a little bit sharper and was able to help me a little bit more, whereas this guy is a genuine stayer and likes to go through his gears as we go along," Purton said.
"His body weight is up a little bit on what his fighting weight is and he's had that gallop this morning.
"He'll have that race at Caulfield and by the time he gets to Flemington he should be right on the mark.
"He was pretty fit before he came out here and it's just the fine-tuning stuff."
Purton says the tempo of Saturday's race will determine Fame Game's chances, saying the faster they go the better he will perform.
However he believes the 3200m of the Melbourne Cup is where Fame Game will be better suited.
"I think it's going to be too short for him, especially with the feel he gave me this morning and what I've seen of the horse before," Purton said.
"He's a really good horse and he's got the ability to win the Caulfield Cup and if the race is run to suit he's going to get his chance, but I feel he's going to be better when he gets to 3200 metres."
Purton doubts he will return to Melbourne for the Cox Plate meeting at Moonee Valley and the Derby Day meeting in between his Caulfield and Melbourne Cup appointments.
Hong Kong officials will undertake a review of their policy on jockeys riding overseas at the end of November. Purton and Joao Moreira rode in Sydney on October 3 but missed a Sha Tin meeting the following day when a typhoon prevented their plane landing in Hong Kong.
New Zealand stayer Mongolian Khan heads the Caulfield Cup market from Japanese visitor Fame Game.
The final field of 18 for the 2400m race will be declared today with the barrier draw held in the early evening. The Murray Baker-trained Mongolian Khan firmed to $4.40 for the cup with his eye-catching third in Saturday's Caulfield Stakes.
Former favourite Fame Game is at $8 while last year's runner-up Rising Romance is an $11 chance.
Mongolian Khan proved his long-distance credentials with wins in the NZ Derby and the Australian Derby earlier this year.
-AAP