Happy Trails has won a Group One race at Flemington at each of the past three spring carnivals.

On Saturday, the eight-year-old gets a chance to make it four when he tackles the Makybe Diva Stakes (1600m).

In his past two spring campaigns, Happy Trails has progressed from a second-up run in the Memsie Stakes to the Underwood Stakes at Caulfield, finishing fourth in 2013 and a close second last year.

But an alteration to the spring calendar has convinced trainer Paul Beshara to include the Makybe Diva Stakes in his stable star's Cox Plate program for the first time.

"We normally used to go from the Memsie to the Underwood but they've changed the date for the Underwood and it doesn't suit us now," Beshara said.

Happy Trails again has the Cox Plate as a spring target, while he is also being considered for a Melbourne Cup start.

The $3 million earner was a last-start 12th in the Memsie Stakes when he was blocked for clear running in the straight and Beshara said the gelding had come on in leaps and bounds since that race.

"He usually takes three or four runs and he comes good," Beshara said.

"His third run usually tops him right off. Last year he ran second in the Underwood at his third run and his condition just gave out. So maybe the mile might be better for him third-up."

Happy Trails has posted his trio of Group One wins in the 2012 Emirates Stakes, 2013 Turnbull Stakes and 2014 Mackinnon Stakes, all at Flemington, a track Beshara believes suits the horse's style of racing.

And Beshara won't be surprised if Happy Trails adds to his tally on Saturday against a star-studded line-up.

"Hell no. He's working well enough to do it," he said.

Memsie Stakes winner Boban is favourite at $4.20 in a field of 16 plus one emergency.

The Chris Waller-trained horse has barrier four, one outside Happy Trails ($11) while last year's Cox Plate runner-up Fawkner has drawn barrier 14.

Fawkner is on the second line of betting at $6 ahead of Australian Guineas runner-up Alpine Eagle at $8.