Racing Queensland stewards continued their blitz on jockeys failing to give their mounts every chance by suspending apprentice Rikki Jamieson for a month on Thursday.

Jamieson is the fourth Queensland jockey to be suspended under Australian Rule 135 (b) since the start of the year.

She pleaded guilty at an adjourned inquiry to a charge arising from her ride on Arms Length at Doomben on July 2.

Arms Length was well backed at $4 before finishing seventh, beaten almost three lengths, behind Write Cheek.

Chairman of stewards Martin Knibbs said Jamieson failed to improve as instructed in the run to the home turn and failed to show expected vigour between the 350m and 150m.

Knibbs emphasised it was not a running and handling charge but rather Jamieson's ride failed to give Arms Length every possible chance to ensure it gained a win or best possible place.

"We aren't saying Arms Length would have won but it might have won or run a place. We will never know," Knibbs said.

Jamieson's suspension will begin on Saturday week and finish on August 20.

Jockeys Rachael Murray, Travis Wolfgram and Brooke Richardson have been suspended for varying lengths of time this year under Rule 135 (b).

Star jockey Damian Browne was also convicted under the charge but had it quashed on appeal.