Tiny apprentice Brooke Richardson swapped baby-sitting duties for a visit to the winners' circle and then a trip to the stewards room at Doomben on Saturday.

Richardson did not have a ride at Eagle Farm races last Wednesday and spent much of the day baby sitting a friend's toddler.

But it was a different story on Saturday when she was the centre of attention in a thrilling finish before figuring in a heated debate in the stewards' room.

Richardson rode an inspired race to land Joint Chiefs ($6) a half-head winner over Prost ($6) in the Iceworks Open Handicap (1350m).

However Tegan Harrison, who rode Prost, protested after being allowed to view the race footage.

"I was denied a run in the straight between Silver Bullion and Joint Chiefs and even when I called out Brooke kept riding and refused to straighten her mount," Harrison said.

Richardson countered that she didn't believe there was a run between the two horses and the problem had been increased by Silver Bullion moving out.

After a lengthy discussion stewards dismissed the objection.

Chief steward Wade Birch said stewards believed there had not been a run at the top of the straight and when one appeared for a few strides Prost had not been able to take the run.

The win was a boost for former western Queensland apprentice Richardson who has only recently returned from a short spell in Sydney.

"It was a real thrill to win today and I hope it will be a boost for me," Richardson said.

Joint Chief has been trained by Brian Wakefield for his entire career but raced by a large number of new owners only for his past three starts.

Wakefield decided to put a syndicate together to race Joint Chiefs after the original owners decided to sell him.

Joint Chiefs now races in one of the most famous sets of colours in Queensland which were worn by Red Seas, top three year old Dual Light and Queensland Oaks winner Aspalita.

"They were the colours of my wife Natalie's grandfather Eric Railton who was a legend in Queensland racing. A couple of other Railtons are also in the horse along with about 20 others," Wakefield said.