Team USA has completed a 5-0 semifinal drubbing of Poland to emphatically underline its United Cup title credentials.

A 6-7 (5/7), 6-4, 10-6 mixed-doubles victory for Taylor Fritz and Jessica Pegula over veteran Łukasz Kubot and teenager Alicja Rosolska rounded out another American clean sweep in Sydney.

Italy advanced to the final after achieving an unassailable 3-1 lead in its semifinal against Greece.

The US will enter Sunday's final having dropped only two rubbers out of 20 in its four ties so far at the mixed-teams event.

Their tie was already sealed before the mixed doubles rubber after Fritz edged Hubert Hurkacz 7-6 (7/5), 7-6 (7/5) in two tight tie-break sets earlier on Saturday to give the US a 3-0 lead.

Madison Keys then routed Magda Linette 6-4, 6-2 to remain unbeaten in four Cup singles matches, before Fritz and Pegula rallied from a set down to complete the whitewash under a closed roof at Ken Rosewall Arena.

The US had enjoyed a commanding 2-0 overnight buffer after singles wins on Friday for Pegula and Frances Tiafoe.

Pegula was particularly impressive in defeating world number one Iga Świątek 6-2, 6-2.

Italy only needed to win one rubber on Saturday after singles victories on Friday night for Martina Trevisan and Lorenzo Musetti.

But world number four Stefanos Tsitsipas got Greece on the board with a 4-6, 7-6 (7/2), 6-4 victory over 2021 Wimbledon finalist Matteo Berrettini.

However, Italy booked its place in the final when Lucia Bronzetti put away Valentini Grammatikopoulou 6-2, 6-3 in the second women's singles rubber.

AAP/ABC