American star Coco Gauff defeated world No. 2 Iga Swiatek 6-3, 6-4 on Tuesday, sealing her spot in the semifinals of the year-end WTA Finals in Riyadh, Saudi Arabia.

Iga Swiatek and Coco Gauff are far from strangers. Swiatek had won 11 of their 12 matches before Tuesday's WTA Finals match. However, it quickly became clear that today's match would be more competitive.

Gauff’s US Open defeat was the camel that broke the straw’s back in her partnership with Gilbert. She hit 19 double faults during her fourth-round defeat and Gilbert was forced to sit through a damning analysis of his player’s serve during a TV appearance.