Shenzhen: Late entry Kiki Bertens stunned world number one Ashleigh Barty with a comeback three-set victory to shake-up the season-ending WTA Finals in Shenzhen Tuesday.
All four players can still qualify from Red Group after Belinda Bencic's three-set victory over Petra Kvitova in the later match. Bertens looked in deep trouble at a set and break down, but turned the tide with ruthless returning and aggressive play at the net to overwhelm a deflated Barty, who could have sealed a spot in the semi-finals with victory.
The world No.10 won 3-6, 6-3, 6-4 in two hours and nine minutes in a see-saw match featuring 12 breaks of serve.
"Of course you're always ready to play, but I did not see it coming today," Bertens said of her late call-up. "In the beginning I was struggling. As the match continued, I felt better and better."
Bertens was a late replacement for world No.3 Naomi Osaka, who earlier in the day withdrew from the round-robin tournament due to a shoulder injury.
She appeared nervous under the bright lights dropping her first three service games and Barty, who has locked up the year-end No.1 ranking, pounced to run away with the first set.
Barty then endured her own service woes against an increasingly aggressive Bertens, who showcased a soft touch at the net. A slumping Barty had her serve broken five times through the second and third sets as Bertens stormed to her first victory over the Australian.