New Zealand rugby great John Kirwan has denounced the ex-Wallabies calling for the head of Rugby Australia boss Raelene Castle, saying former All Blacks would never air dirty laundry in public.

Kirwan also launched a fierce defence of Kiwi compatriot Castle, saying 17 years of ongoing mismanagement is to blame for RA's teetering financial state.

Former All Black winger John Kirwan says New Zealand needs Australian rugby to be strong. Credit:Alden Williams

Former Wallabies Rod Kafer and Nick Farr-Jones have been critical of Castle in the past week since the chief executive revealed the chasm the organisation finds itself in.

A group of former Wallabies are reportedly agitating for change, with Phil Kearns believed to be a favoured replacement as CEO. Former Wallabies captain Kearns has denied having designs on the top spot.