Coco Gauff and Iga Swiatek are on a collision course for United Cup glory after the USA and Poland won their respective semi-finals on Saturday in Sydney.

Swiatek beat Elena Rybakina to help last year’s runners-up Poland see off Kazakhstan and they were joined in Sunday’s final of the mixed-teams tournament by the Gauff-led United States. “I woke up so late today,” said World No. 3 Gauff, 20, after she dismissed Karolina Muchova 6-1, 6-4 to underline what a threat she will be at the Australian Open starting next week.