With confirmation that Serena Williams will not play for the remainder of 2017, there is a G.O.A.T.-shaped hole to be filled on the WTA Tour.
The 23-time grand-slam winner confirmed on Wednesday she is pregnant with her first child.
Williams is aiming for a return to competitive action in 2018, having apparently won the Australian Open while carrying her baby if a "20 week" timeline she suggested in a since-deleted Snapchat post is accurate.
The American is likely to spend an entire grand-slam cycle - if not longer - away from the court, so Omnisport's Matthew Scott looks at who is best-placed to fill her mighty shoes as top dog.
Lest we forget, the German is world number one as Williams begins her sabbatical.
@serenawilliams!! You will be such an amazing mother and I wish your family health and happiness for the best journey in the world— Angelique Kerber (@AngeliqueKerber) April 20, 2017
After a difficult start to 2017, Kerber has begun to regain her form and reached a first final of the year in Monterrey last time out.
Kerber fell at the first hurdle at the Madrid and Rome Masters in 2016, as well as the French Open - leaving a glut of rankings points up for grabs if she can get her game together on clay this year.
Don't @ me.
The only player Sharapova has ever suffered a continued struggle against is... Serena Williams.
Sharapova holds career head-to-head advantages over Kerber (4-3), Venus Williams (5-3), Karolina Pliskova (1-0) and Garbine Muguruza (3-0) - each of the non-Serena grand slam finalists since she was suspended from the game.
And with her return from a doping ban coming just as her great rival is stepping away from the limelight, it gives the 30-year-old another motivation ahead of her comeback in Stuttgart next week.
Arguably no player on the WTA Tour currently has as much upward momentum as the world number seven.
In the space of two years, Konta has gone from world number 151 to breaking the top 10, with her sights already set on the very top.
After securing the biggest win over her career against Caroline Wozniacki in the Miami Open final, Konta said: "I play smart tennis and calmer tennis, I think."
Konta's three WTA titles have come in the past nine months and she has only lost one final to date, proving her burgeoning big-game temperament.
With two titles to her name already in 2017 backing up last year's run to the US Open final, Pliskova has risen to a career-best ranking of third in the world, leaving her in pole position to challenge Kerber for top spot for the time being at least.
Like the German, Pliskova will have plenty of points to make up on during the clay season and only a second-round defeat in Dubai blots an otherwise solid copybook from 2017 so far.
Wins over fellow top-10 players in Brisbane, Qatar and Indian Wells suggest the Czech has the appetite for the big occasion.
The Belarussian has as far to go to reach the top as anybody in this selection, Sharapova aside, but Azarenka's progress will be fascinating, once she returns to action after giving birth to her first child.
Today I had my hardest fight and my very best victory! Our son was born healthy and happy! So thankful and blessed! Thank you pic.twitter.com/zsoFRivnvQ— victoria azarenka (@vika7) December 20, 2016
Victories in Indian Wells and Miami last year - which included wins over Kerber and Serena - hinted that the two-time major winner was back to her best.
Azarenka has won seven of her nine career meetings with Kerber and is one of few players in possession of power even remotely similar to Serena.
If the 27-year-old can hit the ground running, it will suggest that Serena can too, so any of the above will have to be quick if they are to make the most of the WTA Tour queen's absence.
24 de abril 2017
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|Wildcard Yastremska bagels Petkovic in first WTA win|
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|Osasuna forced to design new kit for Barcelona clash|
|Blind happy to play wherever Mourinho needs him|
|Stokes stifles Mumbai to end winning streak at six|
|Oscar De La Hoya wants Anthony Joshua in U.S.: ´This is where he should be fighting!´|
|DeMarcus Ware re-signs with Cowboys to retire as part of team|
|AFC Champions League Review: Al Ain beat Zob Ahan, Al Hilal progress|
|Roma seal deal for Sevilla sporting director Monchi|
|Aguero and Silva train with Manchester City after Wembley injuries|
|Former South Africa seamer Tsotsobe charged with match fixing|
|Wijnaldum urges Liverpool to keep fighting|
|Chernova stripped of Olympic bronze after further doping violation|
|Conte: FA Cup win over Tottenham will not benefit Chelsea in title race|
|Messi feels Clasico win an important step towards LaLiga glory|
|Inter give Pioli vote of confidence|
|´World´s oldest number one´ Serena posts message to unborn baby|
|Former Lions lock O´Callaghan signs new Worcester deal|
|Messi is not selfish – Conte shoots down Fabregas over Hazard advice|
|Allegri: Juventus not perfect yet|
|Wrist injury rules Cibulkova out of Stuttgart Open|
|Zidane has no regrets over playing Bale in Clasico|
|Ibrahimovic is privileged physically - Herrera|
|Vitali Klitschko backs his brother in what could be last-chance saloon|
|Lahm desperate for DFB-Pokal glory before retirement|
|McQueen among uncapped trio in England squad|
|Bojan revels in landmark strike against Bayern|
|Schalke laugh off Liverpool interest in Kolasinac, Meyer and Goretzka|
|Lyon ready to ´go crazy´ to keep Lacazette – Aulas|
|Sharks centre Esterhuizen hit with six-week ban|
|Renault boss rules out doing ´crazy things´ to tempt Alonso|
|Mata could return for Manchester United season finale|
|We´ve let him down – Ramsey wants FA Cup win to repay Wenger|
|George Burgess hit with four-match ban|
|Five finals between Monaco and Ligue 1 glory – Falcao|
|Pacquiao ´not done yet´ with boxing|
|Martial ´a new player´ as Mourinho hails Burnley performance|
|Malinga named in Sri Lanka Champions Trophy squad|
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|Czech Republic international Rajtoral dead at 31|
|#Messi500 breakdown: How Clasico winner took Messi to new heights|
|This is where he should be fighting! – De La Hoya wants to take Joshua to US|
|Cavs sweep Pacers, Rockets poised to advance|
|Stanley Cup playoffs three stars: Capitals avert crisis, take care of Leafs in classic|
|Rockies sweep Giants, Tigers win easily|
|Marcelo: Madrid not inferior to Barca after Clasico loss|
|New Zealand regain trio for Champions Trophy|
|MLS Review: Larin brace sinks NYC, Dempsey stars for Sounders|
|Thunder´s Westbrook chides reporter after loss|
|Clasico hero Messi a blessing for Barcelona, says Iniesta|
|The best player in history – Suarez congratulates Messi|
|Warriors´ Kerr noncommittal about return to postseason|
|NBA needs to control rowdy fans or else I have to protect myself - Beverley|
|Carvajal: Ramos red card defined Clasico and Madrid loss to Barca|
|Gabriel gives Windies hope on landmark day for Younis|
|Messi cannot surprise anyone – Rakitic lauds Barcelona hero|
|Sergio Ramos feels red card was excessive: I did not try to hurt Messi|
|Chappell finally wins on PGA Tour with victory at Texas Open|
|I don´t understand your question - Wenger unsure of impact from semi-final win|
|Giving up is not an option - Injured United star Ibrahimovic vows to return|
|Pique: Ramos will realise he deserves his red once he gets home|
|Belarus to face USA in Fed Cup final as Czech reign ended|
|Zidane: Real Madrid should have been smarter with 10 men|
|Lyon 1 Monaco 2: Falcao and Mbappe make the difference|
|Messi is decisive even when he´s eating dinner at home - Luis Enrique hails Barca star after Clasico|
23 de abril 2017
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|Kante named PFA Player of the Year, Alli retains Young Player of the Year award|