Novak Djokovic said he would step away completely from the Professional Tennis Players Association, citing concerns over transparency and governance within the organisation.
Serena Williams has re-entered the tennis anti-doping testing pool but the 23-times Grand Slam champion denied on Tuesday that the move had anything to do with her making a return to the sport she dominated for nearly two decades.
Novak Djokovic said the shortness and timing of Jannik Sinner's ban this year for an inadvertent doping violation was "odd" and the case would hang over the four-time Grand Slam champion like a cloud for the rest of his career.
Jannik Sinner beat defending champion and Spanish second seed Carlos Alcaraz to win his first Wimbledon title.
Carlos Alcaraz distanced himself from the class-action lawsuit filed by the Professional Tennis Players' Association
Poland's Swiatek, who has dropped to fifth in the world rankings, has so far failed to win a title this year despite a few deep runs in tournaments, including the Australian Open semi-finals.
Yannick Thivant, Thomas Brechemier, Gabriel Petit, Thomas Setodji and Hugo Daubias are the players sanctioned, with the punishments linked to a criminal case heard in 2023 involving a match-fixing group in Belgium, the ITIA said.
Novak Djokovic expressed his frustration at being "kept in the dark" about world number one Jannik Sinner's doping case, saying in Brisbane on Sunday that it was not a good look for tennis.
'I've never been a fan of division in our sport, but I've always fought for better representation and influence of and positioning of the players globally in our sport, which I think is still not where I think it should be.'
'We have exhausted all options for reform through dialogue, and the governing bodies have left us no choice but to seek accountability through the courts.'
Tennis Australia said the ITIA confirmed the breach related to the use of a prohibited method rather than the presence of a prohibited substance.
Novak Djokovic said a majority of players believe favouritism is at play in the tennis anti-doping system.
Rather than face the prospect of a lengthy ban, with a decision expected by the end of the year, World No 1 Jannik Sinner accepted the three-month suspension which will allow him to return before the French Open.
The sanctions are linked to a criminal case heard in 2023 involving a match-fixing syndicate in Belgium over which Bulgarian official Stefan Milanov and French player Leny Mitjana were suspended earlier this year.
The Pole accepted a one-month ban that ended on December 4 after accounting for time already served.
WADA has appealed to the Court of Arbitration for Sport against an independent tribunal's decision in August to clear world number one Jannik Sinner of wrongdoing after he failed drug tests
Sinner fired both team members last month, before winning the US Open title to make it two Grand Slam trophies in 2024 following his breakthrough Australian Open triumph.
Sinner gives the impression of a player with all the answers against whoever he comes up against, but the off-court questions he is likely to face about the doping case that surfaced in August might be harder to shrug off.
Factbox on Italy's Jannik Sinner, who beat Germany's Alexander Zverev 6-3, 7-6(4), 6-3 in the Australian Open final
Sinner remains the man to beat at Melbourne Park even as doping officials seek a two-year ban for the world number one for failing two drugs tests last March.
Iga Swiatek tested positive in an out-of-competition sample in August but the ITIA accepted that it was caused by contamination of her medication melatonin.
Simona Halep questioned the "big difference" in how doping cases are treated after world number two Iga Swiatek was handed a one-month drugs ban
Jannik Sinner overpowered American Taylor Fritz in the final to become the first Italian man to win the US Open singles title.
'I guess only the top players' images matter. I guess only the independent tribunal's opinion on the top players is taken as sound and right.'
Jannik Sinner will hope to block out a rocking home crowd on Sunday when he faces Taylor Fritz in the US Open final at Flushing Meadows, where the 12th seed will be bidding to become the first American man in 21 years to win a Grand Slam singles title.
'Now, because of these mistakes, I'm not feeling that confident to continue with them. I was struggling a lot in the last months. I was waiting for the result. The only thing I need right now is some clean air.'
Images from the US Open men's singles first round matches, at Flushing Meadows, New York, on Tuesday.
The hearings at the Lausanne-based Court of Arbitration for Sport (CAS) are expected to run until Friday. The court said it was unclear when a ruling might be rendered.
Simona Halep has been banned until October 2026 for two separate anti-doping rule violations
Simona Halep is unsure if she will play again if the Court of Arbitration for Sport (CAS) does not uphold her appeal against a four-year doping suspension, the Romanian former world number one has said.
Former Wimbledon and French Open champion Simona Halep had her four-year doping ban cut to nine months.
The 36-year-old was involved in match-fixing with two Algerian players
Images from the US Open men's singles second round matches, at Flushing Meadows, New York, on Thursday.
"Simona Halep, a 31-year-old Romanian tennis player, has been provisionally suspended under Article 7.12.1 of the 2022 Tennis Anti-Doping Programme (TADP)," the body said in a statement.
'The ITIA accepts that the player did not intend to cheat, that his violation was inadvertent and unintentional, and that he bears no significant fault or negligence for it.'
The International Tennis Integrity Agency (ITIA) said it is investigating two matches from this month's Wimbledon Grand Slam after bookmakers flagged "possible irregular betting patterns".
Russian player Yana Sizikova has been released from police custody a day after being arrested at the French Open over match-fixing allegations related to last year's tournament, her lawyer said on Friday.