Fifth seed Ana Ivanovic was knocked out of the Australian Open first round on Monday when she was upset by doubles specialist Lucie Hradecka 1-6, 6-3, 6-2.
The 21-year-old pushed her all-time gold medal haul at world championships to a record 14 when she claimed top honours in the floor exercise for her fourth gold in Doha.
Two former French Open champions produced easily the best women's match of the tournament so far.
Top seed Ash Barty rallied from a set down to power into the semi-finals of the Cincinnati Masters on Friday.
Three Kazakh weightlifters have been stripped of the gold medals they won at the 2012 London Olympics after failing doping tests, the International Olympic Committee said.
Bianca Andreescu is the first Canadian to win a major in the professional era.
French writer Patrick Modiano has won the Nobel Prize for Literature, The Swedish Academy said on Thursday.
Russia's Svetlana Kuznetsova raced to a 6-2, 6-1 victory over Australian Daria Gavrilova to defend her Kremlin Cup title in Moscow on Saturday and secure a place at the season-ending WTA Finals.
Azarenka punished her Russian opponent's weak serve to wrap up the final in 80 minutes in relentless humidity under a searing sun in the early afternoon encounter on the Key Biscayne hardcourt.
Indian tennis stars Sania Mirza and Rohan Bopanna advanced to the quarter-finals of the women's and mixed doubles events respectively after notching up contrasting victories with their partners at the Australian Open.
American Madison Keys overcame late leads by Svetlana Kuznetsova in both sets to defeat the Russian for the Cincinnati Masters title on Sunday.
Svetlana Romashina's jaunty Marilyn Monroe-inspired free routine secured her third gold medal of the world championships and made it four out of four for synchronised swimming's dominant nation Russia.
Russia took a commanding 2-0 lead in the Fed Cup final on Saturday after top 10 players Vera Zvonareva and Svetlana Kuznetsova overpowered their Spanish rivals to put the holders within reach of a fourth title in five years. World number nine Zvonareva beat Anabel Medina Garrigues 6-3, 6-4 in the opening rubber of the five-match tie on Saturday before Svetlana Kuznetsova dismissed 20-year-old Carla Suarez 6-3, 6-1.
Former World No 1 Caroline Wozniacki reached the quarter-finals of Eastbourne's Aegon Championships with a topsy-turvy defeat of Svetlana Kuznetsova on Wednesday.
Russian tennis player Svetlana Kuznetsova blamed politics for the decision to ban her country's track and field athletes from the Rio Olympics and said it was unfair to group them all together as doping cheats.
Svetlana Kuznetsova dug deep into her reserves to overcome Agnieszka Radwanska 7-5, 1-6, 7-5 in their WTA Finals round robin opener on Monday, the late-arriving Russian upsetting the defending champion in a thrilling encounter.
Twice Grand Slam winner Svetlana Kuznetsova and 14th seed Elena Vesnina posted hard-fought, straight-set wins in Friday's semi-finals to set up an all-Russian final in the BNP Paribas Open at Indian Wells.
Former World No 1 Azarenka, the winner of two Australian Open titles and twice a US Open runner-up, withdrew from last year's tournament at Flushing Meadows because of a child custody battle.
Simone Biles claimed a record-equalling 23rd medal at the gymnastics world championships on Saturday, leading an American one-two finish in the vault final in Stuttgart.
By losing, Ostapenko joins a ignominious group including, as well as Myskina, Steffi Graf, Jennifer Capriati, Svetlana Kuznetsova and Angelique Kerber who all lost as Grand Slam champions on the first run of their defences.
Djokovic continues to lead ATP Rankings
Victoria Azarenka dropped her first set of the tournament on Saturday but recovered to book her place in the last 16 at the U.S. Open after two former Grand Slam champions were sent packing.
Svetlana Kuznetsova opened the defence of her Sydney International title with a comfortable 6-1, 6-4 victory over Irina-Camelia Begu on Sunday as the Australian Open warm-up event suffered a pair of big-name withdrawals.
Russia, last year's runners-up, were unable to call on world number six Maria Sharapova who was injured
Russia underlined their total dominance in the synchronised swimming programme at the world championships on Saturday by completing a sweep of all seven gold medals with victory in the free combination team event.
Chinese veteran Peng Shuai beat American Alison Riske 7-6(3), 6-2 in the final of the Tianjin Open to capture her first Tour title on Sunday.
Serena Williams extended her winning streak to 29 matches when she beat Russian Svetlana Kuznetsova 6-1, 3-6, 6-3 in the quarter-finals to continue her run towards a second French Open title on Tuesday.
India's Sania Mirza and her doubles partner Barbora Strycova from Czech Republic notched up a hard-fought win over Gabriela Dabrowski and Maria Jose Martinez Sanchez to advance to the third round of the Wuhan Open tennis tournament in Wuhan on Tuesday. The Indo-Czech pair, who clinched their second title last week at the Pan Pacific Open in Tokyo, edged out their Canadian-Spanish rivals 3-6, 6-3, 10-5 in the second round match that lasted for an hour and 15 minutes.
A resurgent Svetlana Kuznetsova stunned former World No. 1 Caroline Wozniacki in an absorbing encounter on Rod Laver Arena to reach the quarter-finals of the Australian Open with a 6-2, 2-6, 7-5 victory on Monday.
Caroline Wozniacki moved a step closer to erasing an unwanted footnote from the list of her tennis achievements with victory over Svetlana Kuznetsova in the French Open fourth round on Sunday.
Kuznetsova unable to defend Washington title over 'visa issues'
Former world and Olympic champions Svetlana Krivelyova and Olga Kuzenkova have been banned for two years each for failing drugs tests after their samples were re-examined, the Russian athletics federation (VFLA) said on Tuesday.
Twice Grand Slam champion Svetlana Kuznetsova pulled out of Wimbledon on Wednesday with an abdominal strain.
Former world number one Serena Williams returns to Grand Slam action for the first time in over 15 months, when she goes up against Czech Kristyna Pliskova in the French Open first round.
Venus Williams also went the distance before claiming a 2-6, 6-3, 6-3 victory over Croatia's Donna Vekic.
Venus Williams powered into the Italian Open quarter-finals on Thursday with a dominant 6-1, 3-6, 6-1 victory over fifth seed Johanna Konta.
Natalia Ishchenko and Svetlana Romashina had the crowd cheering before they even entered the pool on Tuesday, extending Russia's monopoly of the sport with a dominating duet win. The team competition begins on Thursday, and the Russians are overwhelming favorites to win in that event, too.
Rafael Nadal beat Alexandr Dolgopolov 6-3 6-3 in the Brisbane International first round on Tuesday to make a successful return to action following two-and-a-half months out due to injury. The Spanish former world number one, seeded fifth, made a sluggish start and fell 3-1 down in the first set against his Ukrainian opponent. But Nadal, 30, won four successive games to clinch the opening set and the 14-times grand slam winner broke twice in the second to see off 2012 Brisbane finalist Dolgopolov in one hour 15 minutes. He will next play Germany's Mischa Zverev.
World No 14 Marin Cilic is through to the semi-finals of the Kremlin Cup after the Croat easily beat Russia's Andrei Kuznetsov 6-2, 6-1 on Friday.
The Serbian second seed's match against France's Adrian Mannarino was delayed because of the epic five-setter between Gilles Muller and Rafael Nadal.