Australia tennis schedule: Osaka vs. Sakkari headlines opening day at United Cup

If it’s a new year dawning Down Under, you can be sure it’s time for those irresistible images of tennis players snapping selfies with all manner of indigenous marsupials.

In Perth, Naomi Osaka and Emma Raducanu cavorted with the quokkas -- in terms of pure, unadulterated cuteness, perhaps the most underrated of the marsupials -- on Rottnest Island.

“It’s amazing to see a quokka for the first time,” Raducanu said. “I wish I could have stayed longer.”

Said Osaka, “It’s a beautiful island. I’m really happy I was able to come.”

On New Year’s Eve, they were merely fellow tourists, enjoying the summer sun, the beach and those adorable critters. On Friday night in Perth, Osaka and Team Japan will be in action against Team Greece as the fourth United Cup opens play.

Eighteen countries featuring both women and men will compete for nearly $12 million in prize money in Perth and Sydney from Jan. 2-11. The United States is the defending champion.

Canada and China, who will meet in Sydney on Sunday, spent some time at the Sydney Zoo, where koala bears and kangaroos offered some captivating photo opportunities.

"I’m really excited,” said Canada’s Victoria Mboko, currently ranked at No. 18 -- one spot lower than her age. “This is my first time playing such an event and playing the whole Australia swing, so there are a lot of new experiences and so many new things to come. I’m excited to play United Cup.”

United Cup: Scores | Standings

Two other WTA Tour Driven by Mercedes-Benz events also begin this week, the Brisbane International 500 on Sunday and the ASB Classic in Auckland, New Zealand on Monday.

Friday’s marquee matchup features Osaka, a four-time Grand Slam champion, playing her first match at the United Cup, against UC veteran Maria Sakkari. Osaka has had uncommon success Down Under, winning a pair of Australian Open titles, in 2019 and 2021.

After giving birth to a daughter in the summer of 2023, Osaka has seen her ranking rise consistently to the present position of No. 16. A run to the semifinals of the 2025 US Open signaled that she may again be ready to challenge for the title in Melbourne. The two haven’t met in nearly five years, but Osaka leads the head-to-head series 3-2, winning their only match in Australia, five years ago in Brisbane.

Sakkari, meanwhile, has a spiffy 6-3 record in United Cup singles play. She finished among the year-end Top 10 players from 2021-23, but is currently at No. 52 after going 25-29 in 2025.

The first match of 2026 pits Jessica Bouzas Maneiro against Solana Sierra; both scored their best career Grand Slam results last year at Wimbledon, reaching the fourth round.

Bouzas Maneiro also advanced to her first WTA 1000 quarterfinal last year in Montreal, losing to eventual champion Victoria Mboko. The 23-year-old Spaniard is ranked No. 42 and claims a 1-0 head-to-head advantage going back to a round-of-16 match two years ago in Madrid.

Argentina’s Sierra, 21, made headlines for that fourth-round result at Wimbledon -- as a Lucky Loser.

Day 1 schedule, Perth, RAC Arena

Group A: Spain (0-0) vs. Argentina (0-0) 

Start Time: (10 a.m. local, 9 p.m. ET)

Women’s singles: Jessica Bouzas Maneiro vs. Solana Sierra

Men’s singles: Jaume Munar vs. Sebastian Baez

Mixed doubles: [10] J. Bouzas Maneiro (ESP) / J. Munar (ESP) vs [14] Marie Lourdes Carle (ARG) / Guido Andreozzi (ARG)

Group E: Greece (0-0) vs. Japan (0-0)

Start Time: (Not before 5 p.m. local, 4 a.m. ET)

Women’s singles: Maria Sakkari vs. Naomi Osaka

Men’s singles: Stefanos Tsitsipas vs. Shintaro Mochizuki

Mixed doubles: [12] M. Sakkari (GRE) / S. Tsitsipas (GRE) vs [13]  Osaka (JPN) / S. Mochizuki (JPN)

Coming Attractions

United Cup/Sydney, Jan. 3-11

Play begins Saturday at Sydney’s Ken Rosewall Arena, which will host the semifinals and finals on Jan. 10-11. Canada, seeded No. 2, Australia (No. 5) and 2024 United Cup champion Germany (No. 6) are the top seeds here. Poland, led by World No. 2 Iga Swiatek and Hubert Hurkacz, is also among the favorites.

Brisbane International, Jan. 4-11

Seven of the Top 10 women are scheduled to play in this loaded WTA Tour 500 event. No. 1-ranked Aryna Sabalenka heads the field and will be defending her 2025 title. Sabalenka is one of three former champions, along with Elena Rybakina (2024) and Karolina Pliskova (2017, 2018, 2020). The highly anticipated draw is Jan. 3.

Auckland ASB Classic, Jan. 5-11

Elina Svitolina and Emma Navarro are the top seeds, but they’ll be challenged by up-and-comers Iva Jovic, Alexandra Eala and Janice Tjen -- who all produced career-best results in 2025. Seven-time Grand Slam champion Venus Williams has accepted a wild card.