United Cup: Naomi Osaka loses in her New Year debut, Stefanos Tsitsipas returns from injury with first victory

On January 2nd, 2026, the United Cup began its first day, with the Perth event leading off, where Argentina from Group A and Greece from Group E each claimed their initial group stage victories.

During the night session of the Greece vs Japan Group E match, current world No. 52 Sakkari took 1 hour and 38 minutes to beat former world No. 1 and current No. 16 Naomi Osaka 6-4, 6-2, securing the opening point for Greece. This was their first meeting in nearly five years (their last encounter was at the 2021 Miami Open), bringing their head-to-head record to an even 3-3.

In the second singles match, Stefanos Tsitsipas showed excellent form, defeating Shintaro Mochizuki 6-3, 6-4 in 1 hour and 22 minutes, clinching the win early for Greece.

Stefanos Tsitsipas

Tsitsipas struggled with back injuries during the latter half of 2025, ending his season early after representing Greece in the Davis Cup in September to focus on recovery. His world ranking has dropped to No. 36. In a pre-match press conference, he expressed feeling refreshed both physically and mentally and hopes to avoid injuries in the new season.

"I indeed spent a significant amount of time on rehabilitation and haven’t been on the court for a long time," Tsitsipas revealed in a pre-match interview. "In the last three or four tournaments of last season, I could barely finish matches, so finding a way to return healthy was crucial."

"After losing at the US Open, my back condition was truly alarming; I couldn’t walk for two full days. My biggest hope for 2026 is to avoid such issues, stay healthy, and complete every match without back problems," he added.

In another daytime Group A match, Argentina swept Spain with a perfect 3-0 record to start strong. Baez (No. 45) defeated Munar (No. 33) 6-4, 6-4 in 1 hour and 43 minutes, giving Argentina the first point and improving their head-to-head to 2-0. This marked Baez’s first Top 50 win since his title in Rio de Janeiro last year. Despite inconsistency in 2025 due to injuries, Baez said he is gradually recovering and confident about returning to form. His highest ranking was No. 18 in June 2024.

Photo of Baez

In the second women’s singles match, Sella (No. 66) triumphed over Borrás Mano (No. 41) in a tough three-set battle lasting 2 hours and 2 minutes, 6-4, 5-7, 6-0, securing Argentina’s first Group A win. Later in mixed doubles, Andreozzi and Carlé defeated Cervantes and Lemos 7-6(6), 6-2, completing a 3-0 sweep for Argentina. This South American powerhouse will face the top-seeded defending champions USA in their next group match.

Zhulin

According to tomorrow’s schedule, the Chinese team will play their first group match. Making her United Cup debut, Zhulin will face Belgium’s Elise Mertens (No. 20), followed by Zhang Zhizhen against Berrettini (No. 42). The mixed doubles lineup is yet to be decided. The Chinese team is led by captain Wu Di, with Zhulin and Zhang Zhizhen as the key players, alongside You Xiaodi, Terigele, and Wang Aoran.

(Written and edited by Wang Fei; photos courtesy of Visual China)