The United States and Britain had also called for China to provide proof of Peng's whereabouts.
Three women in the field have topped the world rankings this season, incumbent Simona Halep and her predecessors Garbine Muguruza and Karolina Pliskova, but none of them have been able to kick on and cement their place as the tour's dominant player.
Jennifer Capriati stunned top seed Serena Williams 6-4, 6-4 in the semi-final of the Rome Masters.
Rafael Nadal thumped Canada's Milos Raonic while to capture his eighth ATP title this season while Serena Williams crushed Romania's Sorana Cirstea in the final of the Rogers Cup on Sunday.
Novak Djokovic took a first unsteady step toward completing the calendar-year Grand Slam on Tuesday as the Serb laboured into the second round of the US Open with a 6-1, 6-7(5), 6-2, 6-1 win over dashing Danish teenager Holger Rune.
Images from all the action on Day 9 at the Australian Open in Melbourne on Wednesday
Number two seed Sharapova will face 13th seed Tatiana Golovin of France on Thursday, who beat Luxembourg's Anne Kremer.
Images from ladies singles quarter-finals on day eight at the All England Club.
The American ace proved too good for the second seed in the fourth round of Wimbledon.
Images from Day 1 of the 2020 French Open, in Paris, on Sunday.
Seven-time grand slam champion Venus Williams advanced to the third round at Melbourne Park on Wednesday with a 6-3, 6-2 win over Stefanie Voegele but conceded she was still troubled by an elbow injury that forced her to pull out of the women's doubles.
Summary of sports events and persons who made news on Monday
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.
Venus Williams beat Jill Craybas 6-3, 6-1 to book her spot in the Japan Open second round.
Serena Williams was forced to go on the attack once again to defend equal prize money after she reached a ninth Wimbledon final in a new record time. The world number one blasted Russia's Elena Vesnina off Centre Court in just 48mins 34sec, the fastest ever semi-final at the All England Club. Vesnina earned 500,000 ($649,000) by making the last four.
Justine Henin and Serena Williams will square up in a battle of former champions at the U.S. Open on Tuesday, while Rafael Nadal and Novak Djokovic headline the action in the men's event.
World number ones Serena Williams, aiming to complete the first calendar-year Grand Slam in 27 years, and Novak Djokovic have been named the top seeds for the US Open championships starting on Monday in New York.
Venus Williams gave a supreme effort in the Fed Cup semi-final against Russia after coming off the high of winning her fourth Wimbledon title but came up short in Sunday's decisive doubles match in Stowe, Vermont.
Serena Williams clinched one of the most dramatic victories of her career on Monday, battling crippling cramp to beat Daniela Hantuchova 6-2 6-7 6-2 in the fourth round at Wimbledon.
The 32-year-old has not played singles since losing in the first round of the Australian Open in January to Spain's Roberto Bautista Agut, after which he underwent hip resurfacing surgery in a bid to salvage his career.
Williams surrendered her Wimbledon crown last July when she lost to the 22-year-old Serb in the third round.
Fourth-seeded Venus Williams outpowered Bulgarian Tatiana Poutchek 6-1 6-2 to move into the second round of the Istanbul Cup on Tuesday.
A day after suffering her heaviest defeat since she was a teenager, Serena Williams was back to her brilliant best as she swatted aside Eugenie Bouchard 6-1, 6-1 in her final round robin match at the WTA Finals on Thursday.
Top seed Simona Halep was pooled with grand slam winners Maria Sharapova and Flavia Pennetta in a formidable looking Red Group for the end-of-season WTA Finals on Friday.
Serena Williams has been vulnerable this Grand Slam season but unbeaten in the year's first three major championships.
IMAGES from the Australian Open on Tuesday.
Factbox on Russia's Maria Sharapova who was banned until January 2018 on Wednesday after testing positive for the banned drug meldonium at this year's Australian Open.
It's French Open time! The tennis world's only clay court Grand Slam begins on Sunday and the best of the best will battle it out.
'I'm not thinking ahead to the Open right now because I am here in Toronto and I haven't really played a hard court match in awhile. I'm thinking I want to get some of this under my belt and the Open will happen when the Open happens.'
Images from Day 1 of the Australian Open in Melbourne on Monday.
She has an unenvious head-to-head record against Serena Williams but tennis' glam girl Maria Sharapova says rivalries not only light up the sport but also extract the best out of an athlete.
World No 1 Williams, 33, could not practise on Friday, still suffering from an illness that left her coughing and spluttering during her three-set semi-final win over Swiss Timea Bacsinszky.
With the whiff of a fifth Wimbledon singles title in the air, grass court predator Serena Williams cut down defending champion Petra Kvitova to move ominously into the semi-finals on Tuesday.
Wimbledon champion Venus Williams was pushed to the limit before beating third seed Jelena Jankovic of Serbia 4-6 6-1 7-6 on Wednesday to reach the US Open semi-finals.
India's Sania Mirza occupies the last seeded place in the women's draw for next week's Australian Open.
Images from Day 3 of the Australian Open in Melbourne on Wednesday.
Kvitova to decide on participation on Friday