James O'Connor is a "young punk" according to former Wallaby full-back Greg Martin who laid into the departing Reds playmaker.
The 25-year-old was released from his contract with the Reds this week and is set to return to Europe where he has a deal with Toulon.
Martin, who won nine caps for the Wallabies, was scathing of O'Connor, highlighting an incident last season when he and Reds teammate and former All Black Adam Thompson got into an argument on the pitch during a game.
"He's an immature tw*t," Martin told Brisbane's Triple M radio, before labelling O'Connor the "Justin Bieber" of Australian rugby.
"A little young punk with one of the greats of the modern game – Adam Thompson – having an argument on the field in front of the world? That says it all, who does he think he is?
"This could be the greatest waste of Australian rugby talent.
"He's played 44 Tests for Australia at the age of 25, [but] hasn't played in the last few years because of his bad attitude.
"A guy that just hasn't matured."