Illawarra businessman Tory Lavalle and brother-in-law Tony Bertucchio, who has had a long-standing interest in racing, have steadily built their stable in recent times, in honour of Mick Lavalle, who passed away in 2014.

Lazzarini had been managing the Lavalle operation and another owner John O'Connor's horses at former trainer Mick Tubman's property. But Lavalle maintained a desire to have a full-time trainer led to the move.

"Brett's done a good job and we left on good terms," he said.

"That's the sort of bloke he is, but he also had his commitments with the other stable and with his business.

"We've just brought four new horses in who are all babies to go with the tried horses we've bought, so we wanted a full-time trainer to come in and bring them through."

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Mountney has a long-standing connection to jockey Winona Costin, who has been working as the stable's No.1 rider. Part of the Lavalle stable is Lamelo, a three-year-old gelding named after NBA talent LaMelo Ball, and Wilkshire, a two-year-old colt named after former Socceroo Luke Wilkshire, who was third in his second trial at Warwick Farm on Thursday.

Lazzarini said he was committed to building up the new stable to 15 horses after Christmas.