Two of Chris Waller's stable stars have been retired with Catkins heading to the broodmare barn and Boban to a new life as a hack.

Multiple Group One winner Boban suffered his second bleeding attack in Saturday's Futurity Stakes which means a lifetime ban in Australia.

Popular grey mare Catkins did not win a Group One race during her career but amassed $2 million prize money from her stakes performances over five seasons.

"It is with a heavy heart that I farewell two of the stable's most accomplished performers and I look forward to following their progress through retirement," Waller said in a statement.

Catkins raced below par in last month's Millie Fox Stakes and after a barrier trial on Monday, her owners, the Ingham family, made the decision she should be retired.

"She has been a great horse to us all and finishes her racing career to embark on what I believe will be a successful breeding career," Waller said.

"Catkins was a winner of 16 starts over her 38 start career, 11 of those wins coming at Group level.

"The winning reception received each time she won when carrying the famous cerise colours of the Ingham Family was always extremely satisfying.

"I must thank the Ingham Family for the trust they placed in me as her trainer."

Boban will be in familiar hands as he retires with five Group One wins and earnings of $2.8 million.

"I wish to take this opportunity to thank the wonderful group of owners as well as the punters and race followers as together we have had a thoroughly enjoyable experience and he will now head to one our track rider's to have any enjoyable retirement," Waller said.