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.
23. Oktober 2017
|Thomas joins Spieth & Johnson in all-American top three|
|Verstappen farce leaves F1´s Austin party with bitter hangover|
|We will fight for Conte – Courtois eager to avoid repeat of Mourinho debacle|
|Bayern Munich´s Muller out for three weeks with hamstring strain|
|NFL announces Justin Timberlake as Super Bowl half-time performer|
|Sainz´s Renault debut ´very close to perfect´|
|It´s like hitting a chef with a knife and fork – Neymar blasts Marseille fans for missiles|
|Folau: Wallabies united despite same-sex vote differences|
|Ashwin & Jadeja return for India v Sri Lanka Tests|
|We all deserved substituting after 30 minutes – Henderson slams Liverpool display|
|Mbappe named Golden Boy ahead of Dembele, Rashford|
|Wiggins buzzer-beater leads Timberwolves past Thunder|
|Neymar: Red card was harsh|
|Chargers, Rams and Jaguars record shutouts|
|Patriots dominate Falcons in Super Bowl rematch|
|Verratti: If I was Neymar, I would´ve lost it much earlier|
|Walters to join Broncos as assistant after Maroons renewal|
|Benzema isn´t overrated, insists Madrid boss Zidane|
|Phoenix Suns fire head coach Earl Watson|
|McVay: Rams haven´t arrived by any stretch|
|Cassano: I could´ve been playing on Mars like Messi and Neymar|
|Neymar red card unfair – Emery|
|Cardinals confident in Stanton after ´gut punch´ Palmer injury|
|Kane can become like Ronaldo and Messi, says Kobe Bryant|
|Truex wins at Kansas as play-off drivers find trouble|
|MLS Review: Portland top west, Earthquakes reach play-offs|
|Triceps injury ends consecutive snaps streak for Browns´ Thomas|
|Job (almost) done: How Hamilton can wrap up F1 title in Mexico|
|All Blacks name four uncapped players for November tour|
|Three to go, three more to win - Hamilton issues rallying call with F1 title in sight|
|Kane pleased with Spurs´ spectacle for NBA legend Kobe Bryant|
|Zidane backs ´player of a generation´ Ronaldo to rediscover goalscoring touch|
|Cavani calls on PSG to keep improving after Classique draw|
22. Oktober 2017
|Hopefully next year the fans won´t come - Verstappen enraged by penalty|
|We can see the fat lady backstage - Wolff delighted as Hamilton nears title triumph|
|Conte agrees with Guardiola and Mourinho over EFL Cup|
|Even the Golden State Warriors lose - Guardiola dismisses City ´Invincibles´ tag|
|I am different to other managers – Why Conte does not fear Chelsea axe|
|Character is key for Cahill as Chelsea chase consistency|
|Marcelo lauds Benzema as Europe´s best striker|
|Pochettino lauds Spurs for delivering in front of Maradona|
|Marseille 2 Paris Saint-Germain 2: Cavani rescues visitors after Neymar sees red|
|Hamilton on brink of F1 title triumph following Austin win|
|Rams rout Cardinals in Twickenham shutout as Palmer suffers broken arm|
|Real Madrid 3 Eibar 0: Super Asensio spares Ronaldo´s blushes|
|Red Sox name Alex Cora as new manager|
|WATCH: Golfer Donaldson celebrates card retention with fully-clothed pool dive|
|Allegri thanks Mandzukic for red card in Udinese rout|
|CAF Champions League Review: Al Ahly advance to final in dazzling style|
|Let´s get ready to rumble! Buffer and Bolt set the stage for US GP|
|Armand double leads Exeter past Montpellier as La Rochelle win big|
|Liverpool deserve to be ninth, says under-pressure Klopp|
|Latham credits Taylor´s calming influence for reverse-sweep success|
|Wrong news - Wenger rubbishes Ozil exit rumours|
|Klopp slams Lovren: I would have stopped Kane getting the ball!|
|Udinese 2 Juventus 6: Khedira hat-trick inspires Bianconeri rout|
|We could have scored more - Two-goal Kane hails ´unbelievable´ Tottenham|
|Tottenham´s Kane one of the best - Pochettino|
|Del Potro retains Stockholm crown to enhance ATP Finals hopes|
|Atletico needed win at Celta, says Simeone|
|Tottenham set Premier League attendance record|
|Tottenham 4 Liverpool 1: Kane double increases pressure on Klopp|
|Centurion Kohli surpasses Ponting but Latham and Taylor thwart India|
|Montella questions VAR, promises ´united´ Milan will deliver|
|Tsonga overcomes Schwartzman to claim Antwerp crown|
|Garcia edges out Luiten for another Valderrama victory|
|Celta Vigo 0 Atletico Madrid 1: Fit-again Gameiro ends visitors´ winless run|
|Du Plessis carried off but Proteas seal whitewash|
|Bishoo snares five as Windies turn tables on Zimbabwe|
|Wenger: Ozil back to his best for dominant Arsenal|