United Cup, Day 5 Preview: Teens Maya Joint and Victoria Mboko face vets Krejcikova and Mertens

Four days into the new season, and—not surprisingly—the players at the United Cup are still finding their feet and form.

Yesterday Casper Ruud followed up a win over Alex de Minaur with a loss to Jakub Mensik. Alexander Zverev, after winning his opening match, lost to Hubert Hurkacz. And the Americans, Coco Gauff and Taylor Fritz, finished the day with 1-1 records in singles.

The most eye-catching results from Day 4 came on the women’s side.

Iga Swiatek won her 2026 debut over Eva Lys of Germany, but the 23-year-old, who had struggled to win games against Iga in the past, pushed her to 6-4 in the third this time.

40th-ranked Jessica Bouzas Maneiro of Spain beat Gauff 6-1 in the first set, and 6-0 in the third.

Maria Sakkari made it two quality wins in a row, over Naomi Osaka and Emma Raducanu. Coming in, she was 0-4 against the Brit.

That takes us to the mid-point of the competition. Here are the group leaders so far:

A: USA

B: China

C: Switzerland

D: Czechia

E: Greece

F: Germany

And here’s a look at what’s happening on a relatively quiet Day 5.

Who’s playing who?

Sydney

Canada vs. Belgium (10:30 A.M. local; 6:30 P.M. ET)

Australia vs. Czechia (5:30 P.M. local; 1:30 A.M. ET)

Perth

Italy vs. France (10:00 A.M. local; 9:00 P.M. ET)

Who to watch

Victoria Mboko vs. Elise Mertens: The 19-year-old Canadian and the 30-year-old Belgian meet for the first time. Each won her opening match, and each should give the other a test.

Maya Joint vs. Barbora Krejcikova: Like Mboko vs. Mertens, this match also pits a 19-year-old (Joint) against a 30-year-old (Krejcikova), and will also be their first encounter. Joint was scheduled to play two days ago, but was ill; hopefully we get our first look at the American-turned-Australian in front of her adopted home crowd.

Alex de Minaur vs. Jakub Mensik: Mensik is just 20, but he has already played, and lost, to De Minaur four times. Getting his first win in front of an Aussie crowd would be a nice way for the Czech to start the year.

Flavio Cobolli vs. Arthur Rinderknech: The 30-year-old Frenchman leads their head-to-head 2-1, but the 23-year-old Italian is the man on the rise.

Who’s going to win?

Canada d. Belgium 2-1

Australia d. Czechia 2-1

Italy d. France 3-0