Folau's latest claim caps off Rugby Australia's year from hell

Rugby Australia's year from hell has been capped off with sacked Wallabies star Israel Folau entering a new multi-million-dollar legal claim against the sporting body just days after it was revealed rugby's broadcast deal is in limbo.

In new court documents, Folau says he is set to lose $14 million (AUD) as a result of his sacking and claims the Wallabies would have put in a "superior performance" if Folau was selected for the 2019 Rugby World Cup and he could have possibly captained "a trophy-winning Wallabies team".

The damages figure has been increased to $14 million from a previous estimate of $10 million, according to an amended statement of claim released on Wednesday.

Folau, a hardline Christian, claims he was wrongfully dismissed by Rugby Australia and Rugby NSW after a controversial Instagram post in April condemning "drunks" and "homosexuals" and warning "hell awaits" them.

In the amended statement of claim to the Federal Circuit Court, Folau details the income he has lost since Rugby Australia tore up his contract.

The list includes estimates of between $450,000 and $1.25 million a year in "post-playing career monetary benefits" over a span of 15 to 25 years.

It also details Folau's belief that he could have earned more if he was selected as Wallabies Test captain in the future.

"Additional post-playing career monetary benefits to be derived from building upon (his) record of achievement ... and two additional Rugby World Cups," the claim states.

"Including a superior performance at the 2019 Rugby World Cup by the Wallabies than what was achieved without Folau, and possible captainship of a trophy-winning Wallabies team."

The Folau news comes just hours after a Sydney Morning Heralrd report revealed Castle had sent an apology letter to World Rugby over the behaviour of the Wallabies squad at the World Cup.

Tournament organisers were said to have been unhappy with a number of the Australian contingent in Japan, including former coach Michael Cheika.

The paper quotes an unnamed source, who reportedly saw Castle's letter, in which she bids to make amends for Cheika's criticism of World Rugby and referees, and presenting a 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.

Cheika revealed after the tournament that he would not seek an extension to the five-year spell he served after the Wallabies were beaten 40-16 by England in the quarter-finals.

The Herald report also said World Rugby had opted not to comment when contacted for a reaction.

On Sunday a media report stated long time broadcasters Foxtel had walked away from the negotiation table with Optus rising as a potential broadcaster from the end of the current contract in 2021.

Castle refused to elaborate on the subject when asked at a media conference in Melbourne on Monday, except to say discussions were ongoing.

"There is always a desire to make sure that we can provide our fans with the best opportunity to view the game and the best access, so that continues to be part of the discussions," she said. "We are here to talk about a great game at Marvel Stadium and that's what we want to focus on, so we will take those commercial negotiations outside of this."