Trainer Liam Birchley has drawn top jockeys Craig Williams and Glen Boss for two of the stable's most promising horses in a heat of the State of Origin Jockeys Series at Doomben.

Williams, representing Victoria, will ride Court Martial Miss and Queensland's Boss will be on Gun Case in Saturday's 1200m-heat.

Court Martial Miss has won her past three starts in Queensland since being transferred from Sydney trainer Gary Portelli.

Birchley has long had a big opinion of Gun Case but the five-year-old has had his share of problems.

"We gelded him before this campaign and he won first-up at Kilcoy but this is a lot harder," Birchley said.

Top kiwi jockey Opie Bosson will represent New Zealand and has drawn Maximilian in the first heat and classy mare Adorabubble in the second.

Tye Angland will again represent NSW in the two heats.

The final day of the four-meeting series will be at the Gold Coast on Boxing Day.

At the halfway point, NSW and Queensland share the lead on 11 points with New Zealand on seven and Victoria on five.