"It was his third run in as many weeks and it was too much for him with the weights he's had to carry," she said.
"He ran second in a qualifying race at Burrandowan the previous start and should have easily won that day.
"I don't think he's a city horse but this race on Wednesday is only a mid-week so hopefully he'll go well."
Fire King, who was scratched from the Benchmark 70 event, drew barrier 10 and will be ridden by Justin Stanley, who had a long and successful association with Cairns when she trained at Mackay.