Victoria's former deputy premier James Merlino will head up the authority behind the contentious Suburban Rail Loop.
His appointment to the position comes after former health minister Martin Foley and ex-police and emergency services minister Lisa Neville were named as chairpersons of Alfred Health and Barwon Health respectively this month.
The Victorian Ombudsman is investigating if the state's public service has been compromised by the hiring of more than 30 former advisers to Premier Daniel Andrews and his ministers.
The rail loop was a signature Labor policy announced before the 2018 election.
It became a contentious issue before last year's poll, with the Coalition threatening to shelve it if it took government.
"Suburban Rail Loop is a critical project for our growing city and state - and as a person of the highest integrity, with a proven ability to deliver complex infrastructure and policy agendas, James Merlino is expertly placed to lead the authority into the next phase of project delivery," a Victorian government spokesperson said on Thursday.
"Mr Merlino has extensive experience in infrastructure construction and commercial contract management, as well as a deep understanding of public administration and stakeholder engagement."
Mr Merlino will start work as the rail loop authority's chair on July 1, with his term set to end on June 30, 2026.
He also serves as superannuation fund Rest's chair and director and as a Hawthorn Football Club director.
The former deputy premier replaces James MacKenzie in the rail loop authority role.
Mr MacKenzie will continue to serve as a director on the Suburban Rail Loop board.