The 18 teams at the United Cup are narrowed down to two: Team Poland, which is led by Top 10 stars Iga Swiatek and Hubert Hurkacz and Team Germany, which needed a pair of comebacks to stay alive Saturday and is spearheaded by Alexander Zverev and Angelique Kerber.

ATPTour.com previews the star-studded championship Sunday at Ken Rosewall Arena in Sydney, where play will begin at 5:30 p.m. local time.

It all comes down to THIS ☝️#UnitedCup @sydney_sider #feelnewsydney pic.twitter.com/KAxigk9l9t

— United Cup (@UnitedCupTennis) January 7, 2024

Iga Swiatek (POL) vs. Angelique Kerber (GER), 5:30 p.m. Sydney time (1:30 a.m. ET)

The World No. 1 Swiatek will meet the German lefty Kerber, who earned the first win of her comeback in a dramatic three-set victory Saturday.

Kerber, a former World No. 1 who is returning from an 18-month maternity layoff, fended off two match points to defeat Australia’s Ajla Tomljanovic in the semi-final round. Kerber's next task? Facing four-time major champion Swiatek in a match that is sure to provide exciting, lung-busting rallies.

“I think I have nothing to lose,” said Kerber, who lost her only meeting with the Pole at Indian Wells in 2022.

Swiatek has dropped just one set all week, with wins coming over Caroline Garcia, Beatriz Haddad Maia, Sara Sorribes Tormo and Zheng Qinwen.  Riding a 15-match winning streak, Swiatek's domination led Germany’s Zverev to joke, “Iga is basically a cheat code at the United Cup a little bit, or has been so far. Hopefully we can change that tomorrow.”

Hubert Hurkacz (POL) vs. Alexander Zverev (GER), not before 7:00 p.m.

Fans at Ken Rosewall Arena will then be treated to a Top 10 showdown between Zverev and Hurkacz, who is aiming for his maiden victory against the German in their third encounter. They have not met since the 2021 Nitto ATP Finals, where Zverev was eventually crowned champion.

The battle for court positioning will be crucial, as both players — each 6’5” or taller — will look to dictate play with first-strike tennis.

“Facing Hubi is obviously very different, two very big servers,” said Zverev, who lost a deciding-set match to Australia’s Alex de Minaur in the semi-finals. “I think probably a lot less running than I did with Alex today, a lot less long rallies. I'm looking forward to the challenge.”

The pair of 26-year-olds are each 3-1 this week in singles action. Zverev, who is No. 7 in the Pepperstone ATP Rankings, is competing in his first final in a team event with Team Germany after wins against Adrian Mannarino, Lorenzo Sonego and Stefanos Tsitsipas. Hurkacz has earned victories against Mannarino, Thiago Seyboth Wild and Zhang Zhizhen to take Team Poland at least one step further from last year's semi-final apperance at the mixed-teams event.

"I'm super proud," said Team Poland captain Tomasz Wiktorowski following his team's final berth. "That was a really tough day in the office. We arrived from Perth two days ago, so that was quick adjustment for us to these courts."

Iga Swiatek/Hubert Hurkacz vs. Laura Siegemund/Maximilian Marterer

A deciding mixed doubles match would be a grand finale for a thrilling second edition of the United Cup. Swiatek and Hurkacz will put their perfect 2-0 record to the test while Siegemund and Marterer will be teaming for the first time this week.

In order to keep Team Germany’s title hopes alive on Saturday, it was Siegemund alongside Zverev who fended off two match points in a Match Tie-break against Team Australia, advancing to the final at 2:19 a.m. Swiatek and Hurkacz partnered to defeat Team Brazil and Team Spain in the round-robin stages.