The China Open has been rocked by successive upsets after world No. 1 Elena Rybakina and second seed Aryna Sabalenka were eliminated within 24 hours of each other in Beijing.
Rybakina suffered her surprise second-round defeat on Saturday before Sabalenka followed her out of the WTA 1000 tournament with a straight-sets loss to Czech player Nikola Bartunkova on Sunday.
Rybakina stunned on first match as world No. 1
The 24-year-old Charaeva, ranked 118th in the world, produced one of the biggest results of her career after recovering from a set down against the reigning US Open champion.
She converted five of eight break points and won 76 per cent of points behind her first serve. Rybakina also struggled with seven double faults during the two-hour, 11-minute contest.
The defeat came in Rybakina's first tournament since she defeated Sabalenka to win the US Open last month and take over the No. 1 ranking.
Bartunkova sends Sabalenka packing
Bartunkova, ranked 34th in the world, produced four aces and remained composed during crucial moments to defeat the four-time Grand Slam champion in one hour and 35 minutes.
Sabalenka had five break-point opportunities in the first set but failed to convert any of them. Bartunkova took advantage and secured the only break she needed to claim the set 6-4.
The Czech then broke early in the second set and held her advantage to complete the biggest victory of her career.
“She’s a legend … so I’m really happy that I won the match,” Bartunkova said after the victory.
China Open loses its top two seeds
The back-to-back defeats mean neither of the tournament's top two women's seeds will feature in the latter stages.
Sabalenka entered Beijing hoping to respond after losing the US Open final to Rybakina, but her early exit continues a difficult run at the China Open. She has never progressed beyond the quarter-finals at the Beijing tournament.
Bartunkova will face Austria's Sinja Kraus in the round of 16.
Meanwhile, fourth seed Mirra Andreeva and fifth seed Linda Noskova both progressed, with Andreeva defeating Polina Kudermetova 6-4, 6-1 and Noskova beating Viktorija Golubic 6-2, 6-1.
Attention turns to the remaining contenders
With Rybakina and Sabalenka gone, the women's draw has opened up considerably as the China Open enters its decisive stages.
The Beijing tournament is the final WTA 1000 event of the season featuring a 96-player singles draw, with the 32 seeds receiving first-round byes.
The shock exits have therefore transformed the complexion of the tournament, leaving the remaining contenders with an opportunity to claim one of the biggest titles of the late-season Asian swing.