It will be a case of catch-me-if-you-can for Zac Purton in the Jockey Challenge as he tries to make the most of early opportunities and open up a break on likely pursuer Joao Moreira.

Amazingly, despite leading the Jockeys' Championship by a wide margin, Purton has just six rides - and they come in the first six races of the 10-race program.

Moreira returns from suspension and starts favourite with his nine rides, and the quality of them will make him very hard to beat. Moreira was an odds-on favourite last night at $1.95, while Purton was on the drift out to $6 after opening at $5.50.

Purton opens the day on Bold Tack before riding Telecom Prince, World City, Joy Together, Archippus and Life Of Beauty.

Although all nine of Moreira's rides are likely to start either first or second favourite, the public seem to be over-betting his mounts at the moment and perhaps that tendency is transferring to the fixed-odds Jockey Challenge market.

If Purton can score on at least two of his rides, he will be hard to run down, but Moreira finishes the day strongly with Tonyboy, Ambitious King and Ensemble - so a small saver might be in order if his odds drift dramatically, as he could storm home after betting has closed.

Karis Teetan is the outsider representing the best value, the Mauritian was $20 last night, and has six rides including David Ferraris-trained trio Amazing Always, Activism and Bear Hero. He also has chances on Dehere's The Love and Sky Man.

Olivier Doleuze also appears to have some chance, having firmed from $25 to $17 yesterday, while Tye Angland ($7.50) is the only jockey to have a full book of rides.