With four meetings left in Melbourne for the racing season the jockeys' premiership will go down to wire.

Craig Williams, who has ridden eight winners at the past three metropolitan meetings, holds a two-win lead over Dwayne Dunn who is chasing his first premiership.

Williams looks to have the stronger book including two Godolphin runners, Gridelin and Frothed, in the opening two races.

While Dunn tries to claw back Williams' lead on Wednesday, his apprentice son Dylan will be trying to hold on to his narrow advantage in the battle for the junior title.

He has a three-win lead over Michael Dee who has five rides to Dunn's four on Wednesday's eight race program.