India, Jan. 8 -- After a singles loss and social media drama earlier in the week, Coco Gauff did all her talking on court Wednesday in the United Cup quarterfinals. Gauff won twice - once in singles and then a clinching victory in mixed doubles - to send the Americans into the semifinals in Sydney on Saturday.

Gauff beat Maria Sakkari 6-3, 6-2 to give the defending champion United States a 1-0 lead over Greece. Taylor Fritz, affected by knee tendinitis, had a chance in his singles match to clinch the quarterfinal against Stefanos Tsitsipas, but lost 6-4 7-5. That sent the quarterfinal match to a mixed doubles decider.

In that match, Gauff and Christian Harrison beat Tsitsipas and Sakkari 4-6, 6-4, 10-8. It was on track for a runaway in ...