Top 5 talents collide in Greece vs. Germany QF

Peter Staples/ATP Tour

Four singles competitors, four former Top 5 stars — and each of them will be eager to break back into that elite group in 2024.

Friday's marquee United Cup quarter-final will pit second seeds Greece, led by Stefanos Tsitsipas and Maria Sakkari, against the 16th-seeded Germans, whose hopes rest on Alexander Zverev and Anqelique Kerber. Both teams snuck out of their Sydney groups into the knockout rounds with 1-1 records: Greece topped Group B while Germany's effort was enough to progress despite a second-place finish in Group D.

BOOM! 💥

👋 Friday January 5#UnitedCup pic.twitter.com/qNDD2Ikbn5

— United Cup (@UnitedCupTennis) January 3, 2024

Both Tsitsipas and Zverev ended the 2023 season at the Nitto ATP Finals, though neither advanced to the semi-finals in Turin. Just before the season finale, they contested their 13th Lexus ATP Head2Head matchup, with Tsitsipas winning at the Rolex Paris Masters to improve to 9-4 in the rivalry.

The Greek, a 7-6(2), 6-4 winner on that occasion, is expecting another hard-fought battle at the United Cup.

"The matches are always close. He's a great competitor," Tsitsipas said of Zverev, who joins him inside the Top 10 of the Pepperstone ATP Rankings.

"He's been there for more years than any other player in my generation. He definitely knows what's up and what's going on. He's at a good phase of his career...  He's looking good, he's looking sharp. For me that's another occasion to step up my game and show some good quality tennis."

While Tsitsipas has played just one singles match (and one doubles match) so far this season — including a 6-2, 6-3 singles cruise against Canada's Steven Diez — Zverev has already taken the court four times. In two singles matches, Zverev notched a pair of three-set wins against Lorenzo Sonego and Adrina Mannarino. He also split two doubles outings, both alongside Kerber.

Germany's Kerber — the lone former Grand Slam champion among the teams — will be seeking her first singles win of 2024 when she meets Sakkari for the fifth time. The three-time major singles titlist is 3-1 against the Greek, though the pair has not met since splitting two 2021 meetings.

Sakkari, despite a perfect 2-0 singles record in the United Cup group stage (d. Seguel, Fernandez) is wary of her veteran opponent.

"I saw her the other day. She looks very happy," said the Greek. "Obviously she has the experience. Now she has an extra strength after becoming a mum. It's going to be very tough. She's very experienced. It's going to be a challenge, but I'm ready for it."

The winner of this quarter-final tie will meet host Australia in Saturday's semis.