Jessica Pegula and Taylor Fritz will lead the defending champion U.S. squad.

Powered by a deep roster (and escape rooms), the U.S. swept Italy 4-0 to win the inaugural United Cup title.

Pitted against a fellow Top 10-ranked rival, the 25-year-old Fritz prevailed, 7-6 (5), 7-6 (5), to give the Americans an unassailable 3-0 lead over Poland on Saturday in Sydney.

The U.S. prevailed over Great Britain in the Sydney City Final and will next face Poland—also in Sydney. Greece and Italy later advanced to the event's final four.

In Perth, Maria Sakkari earned Greece a City Final place with a 6-1, 7-5 defeat of Belgium's Elise Mertens.

This isn’t to say the new event is a mistake; it’s not. It’s an entertaining curtain raiser before the regular business of the season begins.

"I need hours on court. I need battles like this," Rafa said following his 3-6, 6-1, 7-5 defeat in Sydney Monday.

"Do you approve?" the Pole asked Roger Federer. It inspired the Swiss to tweet for the first time in nearly a month.

Britain took a 2-0 lead over Spain after victories from Cameron Norrie and Katie Swan, while Jiri Lehecka scored an upset over world No. 12 Alexander Zverev.

The American got back to her winning ways at the United Cup—even if in the slightly unfamiliar discipline of mixed doubles.

Great Britain, Switzerland and France also scored wins over Australia, Kazakhstan and Argentina, respectively, to lead their groups.