Nathan Berry will join his twin brother Tommy in the Sha Tin jockeys' room on Sunday after receiving a surprise call-up to ride at the Hong Kong meeting.

Tommy Berry has forged a winning reputation in Hong Kong since his first meeting on April 28 when he claimed a Group One victory for John Moore.

A multiple-horse fall on Wednesday night at Happy Valley resulted in injuries to two jockeys and suspensions have further reduced the riding ranks.

"Nathan will have five rides," Berry's manager Ryan Robert said.

"There is a shortage of lightweight riders and he has rides at 51.5 kilograms and 52.

"I understand it's the first time identical twins have ridden there."

Nathan has seven rides at Randwick on Saturday with Celtic Prince (race one) and Oakfield Commands (race four) rated his best chances of landing a winner.

Tommy Berry has ridden 16 winners from 120 rides during his stay but says he is committed to returning to Australia when the season ends despite an offer to go back next term.

Douglas Whyte, who was involved in the Happy Valley fall, and Australian Zac Purton who was stood down at the meeting and subsequently underwent surgery to remove kidney stones, are also in doubt for Sunday.

Tim Clark, who returned to Australia last month after two seasons in Hong Kong, is on standby to ride at Sha Tin on July 7.