High profile human rights barrister Julian Burnside will launch a bid on Thursday to replace Australian Greens leader Richard Di Natale as one of the party’s senators for Victoria.

But the veteran lawyer is up against stiff competition for the prized seat in the Federal Parliament’s upper house, with two former state MPs among a field of at least six senior Greens also expected to nominate when the contest officially opens today.

Julian Burnside (left) has put his hand up to replace Greens leader Richard Di Natale (right) in the senate. Credit:JAMES ROSS /AAP

Lidia Thorpe, the first indigenous woman to sit in the Victorian Parliament representing the Greens heartland of Northcote in Melbourne’s inner north, could be tough to beat and her former State Parliament colleague Huong Truong also looks set to mount a strong challenge.