The war at the top of men's tennis has deteriorated further after Swiss star Stan Wawrinka's extraordinary letter to ATP Tour council president Novak Djokovic was leaked on Thursday.
The governing body behind the men's professional tour, the ATP, seems set to lurch into crisis after the Open, with suggestions of a player mutiny.
At the annual players meeting in Melbourne on Saturday, players council president Djokovic reportedly voted against extending the tenure of ATP chief executive Chris Kermode, a move that could set off dramatic changes in the tour's direction.
Djokovic wouldn't confirm his vote, citing the meeting's confidentiality. "The decision hasn't been made on the president," Djokovic said.
"Whether there's a renewal or not, it's going to be decided in the next period."
It emerged earlier this week that the 10-man council voted 5-5 on the issue of Kermode's future. Only one of Kermode's supporters needs to fold to force an immediate ATP board of directors vote on the top official's future.
It has now been revealed Wawrinka wrote a letter to council representatives over the weekend on the eve of the Australian Open after hearing what he claims was disturbing rumours.
The Telegraph has since obtained the brief letter and have reported the entire note was sent to the anti-Kermode faction leaders, typed all in capital letters.
"You need to look at the current direction (of the) last 5 years and accept it is good and moving in the right direction," Wawrinka reportedly wrote.
"You cannot be sure it will be better under a new chief executive.
"I did not want to spend time writing this the day before a grand slam here in Australia but I am reading crazy things online about player council voting against the CEO yesterday.
"In the player meeting yesterday Andy Murray stand up and said that no player knows that any vote is happening and no players have been asked their opinion. You emailed us Friday telling us your opinion because of grand slam money and the players' voice of the ATP and that we need to change CEO.
"I completely disagree and know so many players and so many top players that COMPLETELY disagree with this. The sport and ATP are trying and I repeat moving good forward. In player meeting yesterday, it said the players vote for the ATP is at highest marks ever in history. What is the problem?"
The same report has uncovered extraordinary details of the split in the men's tennis game.
It claims the faction calling for change includes council members Djokovic, Vasek Pospisil, John Isner, Sam Querrey and Lu Yen-hsun.
In an extraordinary claim, the report claims there is growing concern the Djokovic faction does not represent the wider views of the ATP Tour.
It comes after superstar Rafael Nadal sensationally whacked Djokovic and the players council for failing to seek his opinion before last weekend's meeting.
"Nobody from the council came to me and asked me my opinion," Nadal said while voicing his opinion that Kermode should remain in charge.
"So I can't have a real opinion on all of this because no one of my representatives came to me and asked me if I am happy with the president or not. (With) some crucial decisions like this, I don't know, I understand that somebody from the council should come to me and ask my position."
Total player prize money on the tour has risen almost 50 per cent to $AUD330 million during Kermode's five-year tenure.
Earlier this week player council member Pospisil helped light the fuse when he sent his own letter to players ranked between 50-100 on the ATP Tour rankings, calling for Kermode to be axed.
"Grand slams which report hundreds of millions of dollars in profit … yet we get less in prize money than 10 per cent of their revenue," he wrote in an email.
"Our system is broken … it's time for a change."