Tomas Machac suddenly retired from his match against Taylor Fritz at the United Cup.

Tomas Machac suddenly retired from his match against Taylor Fritz at the United Cup.

Tomas Machac suddenly retired from his match against Taylor Fritz at the United Cup.

Tomas Machac suddenly retired from his match against Taylor Fritz at the United Cup.

SYDNEY: Coco Gauff and Iga Swiatek will battle for United Cup glory after the USA and Poland won their respective semi-finals on Saturday in Sydney...

Coco Gauff puts Team USA in the box seat to progress to the United Cup final after defeating Czech Karolína Muchová in straight sets.

Coco Gauff puts Team USA in the box seat to progress to the United Cup final after defeating Czech Karolína Muchová in straight sets.

Coco Gauff puts Team USA in the box seat to progress to the United Cup final after defeating Czech Karolína Muchová in straight sets.

Team USA are United Cup champions once again after Taylor Fritz came up clutch in his match against Hubert Hurkacz.

Team USA are United Cup champions once again after Taylor Fritz came up clutch in his match against Hubert Hurkacz.