Mark Zahra has picked up the Group One ride on English in the Manikato Stakes with Sam Clipperton grounded in Hong Kong.

Both Clipperton and fellow Hong Kong-based rider Joao Moreira have been stopped from flying to Australia this weekend because of an approaching typhoon.

Clipperton was to ride English at Moonee Valley on Friday night while Moreira had been booked for French horse Vadamos in Saturday's Cox Plate.

Vadamos' owner John Camilleri will discuss options for a replacement rider with trainer Andre Fabre for the second time with Moreira called on to take over from the suspended Damien Oliver.

The Hong Kong Jockey Club will not allow Clipperton and Moreira travel in case they cannot get back for their commitments at Sha Tin on Sunday should Typhoon Haima affect air travel.

HKJC chief steward Kim Kelly said the club was left with little alternative after taking advice from the weather observatory and Cathay Pacific Airlines.

"Cathay sent out an announcement that they expect delays and cancellations on Friday and into Saturday," Kelly said.

"The club wasn't prepared to take the punt that those delays and cancellations weren't going to impact the situation first-up on Sunday morning."

Kelly said only 18 jockeys were available for Sunday's meeting and if Moreira and Clipperton were stranded in another country because of the typhoon it would but them in an awkward position.

Last year Moreira and Zac Purton sat out a Group One meeting in Hong Kong after their flight from Sydney was diverted to Taiwan because of a typhoon.

"We're very respectful of the situation in Melbourne and the impact on connections down there, but we also have to look after our own business as well," Kelly said.

"I've spoken to (chief steward) Terry Bailey on behalf of Racing Victoria and they were tremendous over this situation."

Kelly says "considerable rain" is forecast for Hong Kong in the coming days on top of 325mm that fell on Wednesday of which 125mm came 2-1/2 hours before Wednesday night's Happy Valley meeting.