Treadmill sessions and a change of diet have been introduced to try to rekindle Japonisme's desire to race.

A Group One winner and consistent performer in elite company as a three-year-old, the gelding now finds himself in the midst of a form slump stretching back to his most recent win in April last year.

Japonisme has only one placing in 14 starts since he won the Group Two Arrowfield 3YO Sprint (1200m), albeit a creditable third in the Group One Manikato Stakes six months later.

The five-year-old has another opportunity to end his losing streak in Saturday's December Handicap (1400m) at Warwick Farm, but trainer Chris Waller is hopeful rather than confident.

"He's certainly the class horse of the race, but he's not the form horse," Waller said.

"He's trained off and lost interest."

Waller has used a variety of strategies to motivate the 2015 Coolmore Stud Stakes winner including stepping him up in distance and back to barrier trials.

"We've also changed his training. He does a bit of treadmill work and there's a change of diet," he said.

While Japonisme has struggled, stablemate and opponent Invinzabeel is aiming for a hat-trick.

Invinzabeel started this campaign with two unplaced runs but has found form with back-to-back wins over 1400m at Rosehill.

"He's been in the right races, the right tracks and he looks in good shape. That's been the method. Nothing changes going into Saturday," Waller said.