Rugby Australia chief Raelene Castle felt compelled to write a letter of apology for the behaviour of the Wallabies squad at the World Cup, according to media reports.
Tournament organisers were apparently unhappy with some of the Australian contingent in Japan, including former coach Michael Cheika, says the Sydney Morning Herald.
The paper quotes an unnamed source, who reportedly saw Castle's letter, in which she tried to made amends for Cheika's criticism of World Rugby and referees, and his general 'us against them' attitude during the tournament.
In particular, Cheika criticised the decision to slap Wallabies winger Reece Hodge with a three-week suspension for a dangerous tackle on Fiji's Peceli Yato, which left World Rugby bosses unimpressed.
After the Wallabies were beaten 40-16 by England in the quarter-finals, Cheika revealed he would not seek an extension to his five-year spell.
The report also says World Rugby had opted not to comment, when contacted for a reaction.
Rugby Australia recently appointed former Chiefs boss Dave Rennie as new Wallabies coach.