Sydney's premier trainer Chris Waller has challenged Brenton Avdulla to emulate Hugh Bowman's expertise on Liapari at Rosehill, in a duel that could influence the jockeys' premiership race.

Waller laid down the gauntlet to Avdulla, who heads into the final city meeting of the season 2-1/2 wins behind Bowman, after booking him to ride the four-year-old in Saturday's Listed Winter Challenge (1500m).

"Hugh Bowman's had the key to him," Waller said on his website preview.

"Brenton hops aboard. He's fighting for the premiership, so we'll see if Brenton can get this horse to work as well as Hughie has."

Bowman saluted on Liapari at Rosehill and Randwick over the last six weeks, but rides the pre-race favourite Gold Symphony.

The Peter and Paul Snowden-trained gelding is one of eight rides for Bowman, while Avdulla has seven.

Waller admitted Avdulla's task was complicated by Liapari drawing gate 11.

"He's drawn awkward, he'll need a bit of luck, but he's a handy horse," he said.

"He gets back and charges home. You can get away with that it in lesser races, whether he can get away with it in a Listed race and win, is yet to be seen."

Avdulla might take heart from guiding Liapari to half of his six career wins, although none were from wider than barrier six.

Waller also has five-year-old mare Elle Lou lining up in the 11-strong field.

She comes in off a last-start third in the Listed Winter Stakes (1400m) on July 15 behind Slightly Sweet - a rival again this weekend - and Man Of His Word.

"She was very close to winning a Listed Race last start and this is just an extra 150 metres so it should be right up her alley," Waller said.