James McDonald has signed off from Sydney racing for the season with a winning treble and confirmation of how valuable he is to Sheikh Mohammed's Godolphin operation in Australia.

McDonald got the best out of Godolphin gallopers Maternal and Cabalistic in their wins at Warwick Farm on Wednesday in what was his final Sydney race meeting before heading overseas.

He also won on the Chris Waller-trained Miss Denni.

McDonald leaves for England 24 hours after riding at Doomben on Saturday where he will be on the fancied Godolphin sprinter Knoydart in the $2 million Stradbroke Handicap.

In line to have Royal Ascot rides for Godolphin, McDonald is expected to be away for two months.

Godolphin's Australian trainer John O'Shea said the departure of his stable jockey would leave a void.

"I'm sure he'll have a good trip but we will miss him and I'm just hoping he doesn't ride too well and the boss wants to keep him," O'Shea said.

McDonald's treble took him to 88-1/2 metropolitan winners for 2014-2015 but he will be long odds to defend his premiership because his lead over nearest rival Hugh Bowman is only 7-1/2 victories.

The first win for Maternal at her second start gave O'Shea reason to think she might be the best progeny so far of the three-time Group One winner Divine Madonna.

Sent out a $5.50 chance in the Cellarbrations Handicap, Maternal raced in behind the leading division before she was urged between the Gerald Ryan stablemates Bubbleberry and Stilettoed Vixen to score a narrow win.

Godolphin won the corresponding two-year-old last year with Abduction, a filly who earned black-type with a Listed win and a placing in the Group Two Wakeful Stakes and O'Shea says he is happy to make a comparison.

"She appreciated ridden just that bit quieter, although she's not quite as quick as (her mum) with her finish," O'Shea said,

"I think she's going to go better with a bit of time and over a mile ... a bit like Divine Madonna.

Cabalistic found his best barrier manners to outstay his opposition in the Tab.com.au Handicap.

In a slogging finish, Cabalistic ($5) got the better of the favourite Maurus ($3.30) and Super Mover after taking no part in a Gosford race last week when he stayed in the starting stalls.