Novak Djokovic’s career stretched to new heights Saturday when the 33-year-old Serbian beat Milos Raonic to capture his 35th title at a Masters 1000 tournament, events rated one rung below Grand Slams. The Western & Southern Open crown extended Djokovic’s record this year to 23-0 and made him the first man to win each Masters 1000 event at least twice.

But for all the effort he expended on court in the week leading up to the U.S. Open, it was top-ranked Djokovic's off-court dealings that captured the attention of the tennis world over the weekend.

The 17-time Grand Slam champion joined forces with Canadian player Vasek Pospisil for a move that sent shock waves through a tennis ecosystem already groaning under the strain of a global pandemic. On Saturday night, the pair launched a breakaway group, separate from the Association of Tennis Professionals, designed to represent the interests of men’s pro tennis players.

The body, named the Professional Tennis Players Association, intends to represent the top 500 ranked men’s singles players and top 200 ranked men’s doubles players. Although it is not nominally a union — it remains unclear if the group would bargain collectively — the PTPA’s purported goal is to provide men’s players with a self-governance structure while looking into tournament rules and regulations, issues of revenue sharing, pensions and medical care, among others, according to the Associated Press.

Unlike many major sports, tennis players are not represented by a union; rather, each player operates as an independent contractor. The 30-year-old ATP organizes the men’s tour and represents players and tournaments jointly, with representatives from both groups serving on its governing board.

Djokovic was the president of the ATP Player Council; Pospisil had been a member for two years. Both resigned over the weekend. In an email reportedly sent to players last week urging them to join the association, Djokovic and Pospisil said they would serve as co-presidents of the group, serving two-year terms.

“It has become clear that, as a player council member within the current structure of the ATP, it is very difficult, if not impossible, to have any significant impact on any major decisions made by our tour,” Pospisil, the 94th-ranked singles player, tweeted Friday.

Less than 24 hours later, the Canadian tweeted a group photo of a few dozen players, standing together on a U.S. Open court announcing the official formation of the group.

No women were pictured, despite loud calls in recent months for more unification among the fragmented sport, the flaws of which were highlighted by the novel coronavirus pandemic.

The new group also lacks support from the two biggest names in the game.

Roger Federer and Rafael Nadal, both of whom sit on the ATP Player Council, registered their opposition to the PTPA on social media Saturday and urged a more unified sport. Their tweets followed a joint statement from the four Grand Slams, International Tennis Federation and both the men’s and women’s tours.

“It is a time for even greater collaboration, not division; a time to consider and act in the best interests of the sport, now and for the future. When we work together, we are a stronger sport,” the statement read.

Federer and Nadal, along with four other members of the player council, wrote and distributed a letter encouraging other players not to sign up for the new group and drawing attention to the vagaries of Djokovic and Pospisil’s proposal.

“What additional leverage do we have? What is the contingency plan to protect us if this goes ahead and badly?” the letter asked.

During a media day Saturday ahead of the start of the U.S. Open on Monday, players fell on both sides of the dividing line. Many said they needed more time to consider their options before signing on with Djokovic and Pospisil.

One early supporter was Raonic, Saturday's Western & Southern Open runner-up and a 2016 Wimbledon finalist.

The 18th-ranked player said he didn’t view the PTPA as a retaliation against the tour but rather an opportunity for players to explore their options. He expressed disappointment in the opacity of the current system and mentioned tennis executives not taking pay cuts during the pandemic while lower-ranked players suffered a substantial financial drought.

He also said the new group should seek to involve pro women's players.

The exclusion of women on tour was one of the reasons three-time Grand Slam champion Andy Murray said he would not initially support Djokovic and Pospisil’s proposal. On Sunday, Pospisil tweeted “there is active dialogue with the women’s side.”

Murray, one of the few male players who frequently calls out inequalities in the treatment of men’s and women’s tennis players, also said the current ATP chairman Andrea Gaudenzi deserves more time to address players’ long-standing concerns with the sport’s current structure. Gaudenzi was appointed ATP chairman in October.

“Whether that works out or not would potentially influence me in the future as to which way I would go,” Murray said Saturday. “Also, the fact that the women aren’t part of it, I feel like that would send a significantly — well, just a much more powerful message personally if the WTA were on board with it. That’s not currently the case. If those things changed in the future, it’s something that I would certainly, certainly consider.”

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