Long-time Tulloch Lodge employee Mark Newnham has left the Gai Waterhouse stable amid rumours the trainer is considering a new financial partner.
Newnham has been with Waterhouse for 20 years, firstly as a jockey and track rider and more recently as an assistant to the trainer.
He will apply for a trainer's licence this week but as yet does not know where he might be able to set up.
On Saturday, Waterhouse made no comment on the rumours she was selling Tulloch Lodge to Hong Kong interests.
A day later she used Twitter to deny she was planning to retire.
"I intend on training racehorses at Tulloch Lodge for many years to come," Waterhouse tweeted.
In November, Newnham won the top honour at the inaugural Australian stud and stable staff awards sponsored by Godolphin.