CANCUN (Reuters) - Iga Swiatek beat an out-of-sorts Coco Gauff 6-0 6-4 in windy conditions at the WTA Finals in Cancun on Wednesday to reach the doorstep of the semi-finals and keep her hopes of retaking the world number one ranking alive.
Swiatek came out firing in their group stage match and broke the U.S. Open champion for a second time with a lovely looping crosscourt winner to take a 4-0 lead.
Two games later, the second-seeded Pole pounced on a poor drop shot from the American teenager and blasted a backhand past her to capture the one-sided first set.
Gauff raised her level early in the second, winning three straight games for 3-1 advantage and coming out on top of a marathon service game for 4-2.
But the four-time major champion would not back down, holding at love and then breaking back on Gauff's badly missed forehand into the net for 4-4.
From there Gauff began to unravel.
She threw her racket against the court in frustration after she issued four straight double faults while serving for the set at 5-4 and appeared on the verge of tears in the next game, where she whiffed on a return of serve en route to a love hold.
Swiatek improved to 9-1 lifetime against Gauff when the third seed's overhead landed in the net on match for her 31st unforced error of the contest.
The evening group stage match in the eight-player, year-end Finals will see sixth seed Ons Jabeur battle Marketa Vondrousova.
Swiatek, who lost her world number one ranking to Aryna Sabalenka after September's U.S. Open, will win the group if Vondrousova beats Jabeur and will be through to the semis if Jabeur wins in three sets.