All four players who featured for the United States in the final are inside the world's top 20 - Jessica Pegula (3), Taylor Fritz (9), Madison Keys (11) & Frances Tiafoe (19)The United States beat Italy to win the inaugural mixed teams United Cup.
World number nine Taylor Fritz secured the title with a 7-6 (7-4) 7-6 (8-6) victory over Matteo Berrettini in the third rubber of the best-of-five final.
Earlier, Jessica Pegula beat Martina Trevison 6-4 6-2 before Lorenzo Musetti withdrew from his men's singles rubber against Frances Tiafoe with a shoulder injury after losing the first set 6-2.
Madison Keys put the US 4-0 ahead with a 6-3, 6-2 win over Lucia Bronzetti.
"I was happy to be in that position to clinch the match," said Fritz.
"It's amazing for the team to win this event, we came in with really high hopes.
"When we combine the guys and girls from the US we are so deep through the rankings it just makes the team so much stronger."
The new event began with 18 nations playing round-robin matches in Perth, Brisbane and Sydney.
The United States team lost just two rubbers throughout the entire tournament, including in a 4-1 victory over Great Britain in the Sydney City Final that secured their progress into the last four.
They went on to beat Poland, led by women's world number one Iga Swiatek, 5-0 in the semi-finals, while Italy defeated Greece 4-1 to reach the final.
