Top fillies may clash in Derby

New Zealand's two leading fillies are on a surprise collision course in the New Zealand Derby - and it will cost one of them $22,500 just for a shot at the classic.

Exceptional filly Fix is set to join long-time favourite Habibi in the TV3-sponsored Derby at Ellerslie on March 2, with her connections likely to pay the late entry fee.

While a final decision will not be made until after the Avondale Guineas at Ellerslie on Sunday, co-trainer Ken Kelso says the Derby is now Fix's main focus.

She was originally to be set for the New Zealand Oaks at Trentham on March 16, with victory there guaranteeing her the Filly of the Year title.

But her connections have now decided on a shot at the biggest classic of them all, providing a clash of the two fillies who dominated the three-year-old races at the Ellerslie Christmas carnival.

"The Derby is a very much a target now," said Kelso.

"And if she goes there it will be instead of the Oaks. She won't do both."

Kelso says the change of plan is influenced by several factors.

"We think it might simply be what is best for her, to start with," said Kelso.

"She is unbeaten in three starts at Ellerslie and we are also not entirely sure she is a true 2400m horse.

"But 2400m at Ellerslie is not always the extreme staying test for a 3-year-old that 2400m of the Oaks at Trentham is."

Fix and Habibi share something in common apart from their rampant recent form - jockey Vinnie Colgan.

"That is another issue going forward because Vinnie is committed to Habibi," said Kelso.

"Finding the right jockey at 54.5kg provides its own challenges."

Habibi will be the headline act in this Sunday's Avondale Guineas at Ellerslie and Kelso will be watching with great interest.