Zac Purton has capitalised on some late pick-up rides with four winners at Happy Valley, propelling him to a seven-win lead over rival Joao Moreira in the battle for championship honours.

Moreira started the night with an early win on the Caspar Fownes-trained Daily Beauty before Purton struck back in kind.

Hong Kong's champion jockey last season, Purton quickly added wins on Highland Fortune, Star Shine, Alpha Hedge and Victoriam - all for trainer Francis Lui.

Two of Purton's winners were pick-up rides after Vincent Ho was stood down from the meeting due to illness.

Purton has now ridden 136 winners this season and with Moreira set to miss at least one of the remaining six meetings through suspension, the Australian is in the box seat for a title defence.

Not that he is getting ahead of himself.

"Joao is such a great rider that you can never write him off and it's only a matter of time before he comes out and has a big day," Purton said.

"You've always got to be wary of the wounded."

Lui's four-winner haul gives him 59 winners for the season, just two behind longtime leader Ricky Yui and with a genuine shot at a maiden Hong Kong trainers' title.