New Zealand-trained horses have enjoyed a lucrative time in Sydney so far this carnival but the next wave of Kiwis faces unique challenges as the impact of Covid-19 takes hold.

Australia has joined New Zealand in implementing 14-day self-isolation period for anyone arriving in the country to try to halt the spread of the coronavirus.

While New Zealand horses can step straight into Australia and compete, they will be without their regular handlers unless they were one of a handful of stables to already have staff and horses based across the Tasman.

New Zealand Derby winner Sherwood Forest and third placed Scorpz, were among a shipment of horses set to travel to Sydney from Auckland on Monday night but that flight has been postponed 24 hours.

The two are set to contest Saturday's Group One Rosehill Guineas (2000m) as a lead-up to the Australian Derby (2400m) two weeks later.

"It is going Tuesday night at this stage," Sherwood Forest's trainer Tony Pike told NZ Racing Desk.

"The hold-up was just over the professional grooms getting clearance to be classified as crew, so they can come in and out of Australia and New Zealand. They have had verbal clearance, but the airlines want written clearance.

"I am probably one of the few lucky ones. Marshy (Stephen Marsh) and I have got an established base over there.

"Mark Hills was over there with The Bostonian and Not An Option and I picked Chris McNab (foreman) up on Sunday and sent him back over the Tasman before the isolation period came into effect."

Stephen Marsh's racing manager Todd Pollard is also ensconced at Rosehill, having taken Elisa Carolina over and he is duly awaiting the arrival of Scorpz.

The powerful Te Akau team is headed in Australia by trainer Jamie Richards' father Paul.

Pike said the strange circumstances had also led to the Kiwis looking after each other even more than usual and banding together.

"I had Brent Taylor (owner) ring me to see if we would take Two Illicit over and just slot into our team as (trainer) Roger James can't send any staff over as they would have to quarantine.

"Stephen sent Todd Pollard over last Sunday, so there is Chris, Mark, and Todd over there with five horses and it looks like Two Illicit will end up coming to our base as well.

"Two Illicit will stay in Roger's name and we will just have to train them over the phone."

Pike is pleased with Sherwood Forest and will also have last start Group One Canterbury Stakes winner The Bostonian at Rosehill on Saturday in the Group One George Ryder Stakes.