Here is a player profile, a look at the form and records of American Madison Keys and compatriot Sloane Stephens ahead of Saturday's US Open final (prefix number denotes seeding)
Sahaja Yamalapalli created a major upset at the WTA 125 Abierto Tampico, upsetting former US Open champion Sloane Stephens in the first round.
Factbox on American Sloane Stephens, who beat compatriot Madison Keys 6-3 6-0 to win her first U.S. Open singles title on Saturday:
Tennis star Sloane Stephens and soccer player Jozy Altidore have gotten married.
The 26-year old Stephens and Altidore, 29, announced their engagement on Monday with joint posts on social media.
Madison Keys fought off a late challenge from fellow American Hailey Baptiste to book her spot in the French Open quarter-finals with a 6-3, 7-5 victory at Roland Garros on Monday.
Factbox on American second seed Coco Gauff, who defeated Belarusian world number one Aryna Sabalenka
Yuan broke Stephens when the American was serving for the match at 6-5. Stephens led 5-4 in the tie-break but could not hold on to her advantage and crashed out.
Next up for Osaka is a second round match against Veronika Kudermetova.
Unseeded Sloane Stephens crushed fellow-American Madison Keys 6-3, 6-0 to win her maiden Grand Slam, in the US Open final, in New York on Friday.
Novak Djokovic began his French Open campaign with a comfortable win.
Elina Svitolina stretched every sinew in a brilliant display of defensive tennis to register the biggest win of her career when she rallied for a 3-6, 6-2, 6-2 triumph over Sloane Stephens in an enthralling WTA Finals title decider on Sunday.
Serena Williams has defeated her compatriot in four straight matches since a defeat in the quarter-finals of the 2013 Australian Open.
Madison Keys said she would be wary about being too aggressive against Iga Swiatek.
American Sloane Stephens kept intact her streak of never having lost a final as she defeated Latvia's Jelena Ostapenko 7-6(5), 6-1 to claim the Miami Open title on Saturday.
Aryna Sabalenka opened her bid for a third straight Australian Open title with an easy victory over Sloane Stephens on Sunday.
American Sloane Stephens battled back to defeat defending champion Caroline Garcia at the Cincinnati Open.
Sloane Stephens's US Open win could be the first of many Grand Slam titles for the young American, but there is a question mark on her ambitions, according to former world number one Mats Wilander.
Sloane Stephens watched January's Australian Open from her couch, a large cast on her left foot rendering her immobile and raising questions in her mind about her ability to bounce back from the injury.
Czech reigning champion Marketa Vondrousova, seeded sixth and in the same quarter of the draw as Swiatek, will open against Spain's Jessica Bouzas Maneiro.
Sloane Stephens has denied she was celebrating the shock fourth round exit of World No 1 Serena Williams and said she felt the television footage was intrusive.
While the stakes could not be higher on Thursday, Sloane Stephens said there will be no "weirdness" in the locker room.
Photos of the Australian Open matches
Sloane Stephens ground down unseeded German Julia Goerges 7-5, 6-2 to win the Auckland Classic on Saturday, the American ending a busy day at the office with a confidence-boosting triumph ahead of the Australian Open.
American seventh seed Sloane Stephens captured her third title of 2016 by defeating Russian qualifier Elena Vesnina 7-6(4), 6-2 in the final of the Volvo Car Open clay court event in South Carolina on Sunday.
Serena Williams trounced Maria Kirilenko at the Australian Open on Monday, setting up an all-American quarter-final with her would-be successor Sloane Stephens after Andy Murray had put flagging Frenchman Gilles Simon out of his misery.
Madison Keys is the second-oldest woman to claim her first Australian Open singles title in the Open era.
Serena Williams easily won her eagerly-awaited clash with Sloane Stephens at the US Open on Sunday as normal service resumed at the last Grand Slam of year.
Images from the French Open women's semi-final matches played at Roland Garros on Thursday
Unseeded Sloane Stephens got the better of fellow-American Venus Williams in a thrilling contest to make it to her first Grand Slam final, at the US Open, in New York, on Thursday.
US Open champion Sloane Stephens said she has no pity for Madison Keys after thrashing her 6-3, 6-0 in Saturday's final, given the huge runnersup check her friend will receive.
Stephens used her powerful game to the full in the first set, hitting winners almost at will, but Halep then stepped up a gear and went on to win 3-6, 6-4 6-1.
American teenager Sloane Stephens caused the biggest upset at this year's Australian Open when the 29th seed rallied to overcome an injury-hampered Serena Williams in the quarter-finals on Wednesday.
Aryna Sabalenka will bid for a third Australian Open title in succession as if she was going for her first
Former French Open champion Ana Ivanovic beat Anastasia Pavlyuchenkova 6-3, 7-6 in the first round of the Dubai tennis championships on Monday while US teenager Sloane Stephens was eliminated in three sets to cap a miserable debut trip to the Gulf.
Jannik Sinner begins his Australian Open title defence against Nicolas Jarry while women's champion Aryna Sabalenka takes on 2017 U.S. Open winner Sloane Stephens
One year after shaking off a crippling foot injury to claim a stunning US Open victory, Sloane Stephens said her follow-up season felt just as good as the American prepares to play in next week's WTA Finals for the first time.
Serena had her two biggest cheerleaders by her side, husband Alexis Ohanian and three-year-old daughter Alexis Olympia Ohanian Jr.
Key statistics from American Sloane Stephens' 6-3, 6-0 victory over compatriot Madison Keys
Sloane Stephens was keen to swat away any references to a controversial clash against Victoria Azarenka at last year's Australian Open as the American advanced to a possible fourth-round clash against the two-times champion on Monday.