No. 1-ranked Novak Djokovic and former top-30 player Vasek Pospisil would be the co-presidents of a new group they are trying to set up to represent men's professional tennis players.
A letter emailed to players -- and obtained by The Associated Press on Friday -- pushes the formation of a Professional Tennis Players Association, abbreviated PTPA.
Sent shortly before Monday's start of the US Open, the letter says its objective is "to solicit support from players to form an association with a mandate to promote, protect and represent the interests of its players ... and protect the future of tennis."
Tennis players never have had a union the way North American team sports do. Each player is considered an independent contractor.
"Unlike many other professional sports, men's professional tennis has never had a representative body that is represented for players by players," the email said.
The men's tennis tour is organized by the ATP; the women's tennis tour is run by the WTA. Djokovic is the president of the ATP Player Council and Pospisil has been a member for two years, but he tweeted Friday night that he was resigning.
"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 wrote.
There was talk earlier this year, prompted largely by tweets from 20-time Grand Slam champion Roger Federer, about the possibility of merging the two tours.
This proposal would set up something for just men ranked in the top 500 in singles and top 200 in doubles.
"The goal of the PTPA is not to replace the ATP but to provide players with a self-governance structure that is independent from the ATP and is directly responsive to player-members' needs and concerns," the email said.
The letter said the PTPA would be governed by a board of trustees with up to nine members, elected annually.
The trustees would appoint two co-presidents with two-year terms -- and that first leadership duo would be Djokovic, a 33-year-old from Serbia who owns 17 Grand Slam singles trophies, and Pospisil, a 30-year-old from Canada who won the 2014 Wimbledon doubles title and is currently No. 92 in singles.
Among the areas the PTPA would look into, according to the email: ATP and tournament rules and regulations, revenue sharing, disciplinary actions, pensions, travel, on-site food and amenities, insurance and medical care.
There would be a dues structure with players paying an amount based on their ranking -- from a high in singles of $1,500 for those from 1 to 50 down to $75 for those in spots 401 to 500, and a high in doubles of $1,000 for those 1-30.
The total fees listed in the letter would bring in $317,500 each year.
The email asks players to sign a letter backing the PTPA, and says "if a significant number of players support this initiative we will move forward" with writing bylaws and proposing a board of trustees.
At least one player is on the record as saying he'll sign on: 2016 Wimbledon runner-up Milos Raonic.
"Players have had plenty of time to think and reflect and take a look at certain parts which they may not be happy with and discuss," Raonic said Friday after reaching the Western & Southern Open final.
"A lot of us were kept in the dark by our leadership for six months. We were disappointed with many things. I voiced my opinion on many things, such as ... executives in other sports taking pay cuts to support us. As tennis players, we weren't making a dime for months and months. ... Lower guys weren't making a dime," Raonic said. "But our executives were staying home and didn't feel it necessary to take any pay cuts. I pushed for that on every single phone call we had."
The ATP Tour responded quickly to news of the plan, which is seen by most observers as part of a growing, ongoing attempt by a cohort of players to take over control of the sport -- something the players have already done once, successfully. The ATP Tour was born following the 1988 "parking lot" revolution led by activist players.
The ATP Tour's statement read, in part: "The success of the ATP Tour, and its growth into one of the world's leading sports properties over the past 30 years, has been built upon a true equal partnership between players and tournaments, alongside productive collaboration with the Grand Slams, WTA, and ITF.
"We recognize the challenges that our members face in today's circumstances. However we strongly believe that now is a time for unity, rather than internal division ... we remain committed to working closely with the other governing bodies of tennis as we look to fulfill the true potential of our sport."
Should the players support the plan forwarded by Djokovic and Pospisil, the new group would add yet another acronym -- PTPA -- to a sport that is often criticized for lacking a central governing body. Instead, the "alphabet soup" of entities all try to work together while jealously guarding their own turf and independence.
The ATP Tour has enjoyed tremendous growth in recent years. Attendance has soared and prize money doubled during the tenure of Chris Kermode, who was CEO of the ATP Tour for the five-year period ending in 2019. His contract was not renewed due largely to the discontent of Djokovic and his allies.
One of the main problems faced by those hoping to create a dynamic players' union of the kind that exists in sports like the NBA and NFL is that US labor law considers the tennis tour a monopoly, as a result of which the players are prohibited from unionizing on the grounds that it would concentrate too much power in their hands. If unionized, the players would also be more subject to control of their careers by union regulations.
The lack of any engagement with the WTA also hit a sour note to some at a time when many in leadership positions, including the heads of the ATP and WTA, are expressing greater interest in forming a genuine partnership between the two tours.
Information from ESPN's Peter Bodo and The Associated Press was used in this report.