Still, all four of these players are scheduled to participate in the International Premier Tennis League that kicks off its 2015 season Dec. 2.
Brushed off by the ATP and WTA Tours as a glorified exhibition, theIPTL is back for a second year, and it's bigger. This time, Rafael Nadal,Kei Nishikori and retired greats such as Marat Safin are joining the league.
With the biggest stars playing in front of packed houses in some of the most under-served tennis communities in the world, the ATP and WTAcan no longer ignore the IPTL.
Whether through cross-promotion or by simply including IPTL results on its website, the ATP and WTA need to find a way to embrace what is becoming one of the biggest stories in the offseason.
The IPTL has developed into more than just a traveling exhibition. The matches are competitive and high quality. Most importantly, the events are star-studded and entertaining.
An individual sport, tennis is driven by personalities. When the biggest personalities in the business are promoting and participating in something, fans take notice.
It's not as if the ATP and WTA ignore other non-tour activities. Whether Sharapova is hawking candy, Serena Williams is showcasing her clothing line at New York Fashion week or Federer is pitching Moet at a press junket, the tours cover these players and events.
So if the ATP and WTA have no problem promoting players pitching non-tennis products, why ignore them when they are actually playing tennis?
Besides, the IPTL is not going away. Founded by former tour playerMahesh Bhupathi, the IPTL was designed to be tennis' answer to cricket's International Premier League in India. Similar to the World Team Tennis of the 1970s, IPTL features teams in Singapore, Japan, the Philippines, India and Dubai.
In April, the IPTL held its version of a draft. Top players like Federer and Nadal are reportedly being paid $1 million per match.
The Singapore Slammers feature Novak Djokovic, Nick Kyrgios, MarceloMelo, Belinda Bencic, Dustin Brown, Karolina Pliskova and CarlosMoya.
Federer headlines the UAE Royals. The rest of the roster includes Goran Ivanisevic, Ana Ivanovic, Marin Cilic, Daniel Nestor, KristinaMladenovic and Tomas Berdych.
The Philippine Mavericks are led by Serena Williams, who will be joined by Milos Raonic, Richard Gasquet, Sabine Lisicki, Mark Philippoussis,Jarmila Gajdosova and Filipino-American Treat Huey.
The new Japan Warriors are led by Kei Nishikori and feature Sharapova, who last year played for the Manila Mavericks. The team also includes Kurumi Nara, VasekPospisil, Leander Paes, Daniela Hantuchova, Lucas Pouille and Safin.
Nadal is the headliner for defending-champion Indian Aces. Monfils,Agnieszka Radwanska, doubles specialists Sania Mirza and RohanBopanna as well as Ivan Dodic and Fabrice Santoro round out the team.
Of course the biggest names are getting huge paydays. But it's not all about the money. Players get to test themselves against top competition with little to no pressure. It's a fun way to work on their games and reach out to fans.
Last year, Serena Williams skipped Brisbane. Her only prep for the 2015 season was IPTL and the exhibition Hopman Cup. That approached seemed to work out just fine.
In fact, even some of the young IPTL participants such as KristinaMladenovic, benefit from playing. Mladenovic finished 2014 ranked No. 81. She is No. 27 now. Think of the learning experience she received sitting court-side while watching Williams, Sharapova and Caroline Wozniacki operate. She also got a chance to measure her game against the best without fear of losing rankings points.
For a young ATP player, no amount of coaching or practice duplicate a nothing-to-lose match against Federer, Djokovic, Nadal, Monfils,Gasquet or Nishikori.
Perhaps what irks ATP and WTA officials is that some of the players who are cashing in on this offseason league are complaining about the length of the tours.
Last year, when the IPTL first announced its plans, WTA Melissa Pine, the WTA’s Asia-Pacific vice president and tournament director of last year's WTA Championships in Singapore, spoke with the National about concerns over player burnout.
“But I guess just as a matter with the WTA and players, it’s for them to ensure that they’re striking the right balance in the off-season between capitalizing on promotional opportunities, while at the same time ensuring they have the proper rest and recovery for the upcoming season."
Radwanska recently stated that she would like to see the WTA Tour season reduced. Yet she too will be playing in the IPTL.
Maybe Radwanska wants a break from the grind of back-to-back tournaments and would rather enjoy IPTL-style match play. Matches rarely last longer than 30 minutes, and top players can opt out of venues if they wish.
Opting out contributes to the exhibition feel of the IPTL. However, unlike pre-tournament exhibitions such as kid's day, the IPTL matches are taken seriously. Players are clearly out there to win, and a trophy is awarded to the winner.
Another appeal is how the IPTL brings together present, past and future stars. Each team has young players, established Grand Slam champions, a local hero and past champion.
The league also brings together intriguing pairings fans never see on the tour, such as Gael Monfils and Federer playing doubles or Andy Murray and Sharapova teaming up for mixed doubles as they did last year.
During the season, the legends and champions tours, while staged at Grand Slam events, are largely overlooked by fans. In the IPTL, the past champions matches count toward team success. And then there is something gratifying to players and fans about seeing the game's best talent, past and present, assembled court-side.
The IPTL has certainly won over players who were once skeptical of the new league. Federer, quoted in the Gulf News, "Firstly, I want to see whether it takes off or not...I know a lot of people have invested in it or are part of it. Anywhere where tennis grows is a good thing, so I hope it takes off and becomes very successful."
Early last year, when the league appeared to be struggling to cement deals with big stars, Max Eisenbud, the agent for Sharapova and Li Na, issued an email stating that his clients would not be participating in the league. Li retired, but Sharapova came aboard. Federer replaced Nadal, who had committed but withdrew due to injury.
Using its hashtag #Breakthecode, the IPTL dominated tennis news on Twitter. Players posted selfies in last year's offseason. The IPTL promotes the ATP and WTA, routinely posting updates on its stars in tour events.
Merely staying on the sidelines is probably not a good idea. No formal arrangement is needed. However, when the biggest and brightest stars are tweeting daily pics from the IPTL, how can the ATP and WTAcontinue to ignore?
If embraced properly, the IPTL could enhance, not hurt, the tours.
Perhaps the ATP and WTA should look to the NBA and how it's handled non-sanctioned leagues. Although not sponsored by the NBA, the Drew League is featured on NBA.com. The NBA appears to understand the Drew League keeps its stars in the news in the offseason.
Like the Drew League, the IPTL satisfies the fan's postseason appetite for following the stars.
Instead of ignoring the IPTL, the ATP and WTA should consider embracing the league. After all, they have the similar interests in promoting and growing the game of tennis.