Welcome back to the Monday Tennis Briefing, where The Athletic will explain the stories behind the stories from the past week on court.

This week, the first tournaments of 2025 reached their sharp ends all across Australia and New Zealand. Aryna Sabalenka continued a remarkable record and too many matches were ended by retirements.

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How to beat Aryna Sabalenka in Australia?

On the face of it, there’s little to give the rest of the field hope. World No. 1 Sabalenka comes into the Australian Open as the two-time defending champion, on a run of 27 wins in 28 hard-court Grand Slam matches that took in her first U.S. Open title in September alongside the two Melbourne majors.

She has also won 27 of her last 28 matches in Australia after winning the Brisbane International title on Sunday, staying strong in an event in which 10 of the 16 seeded players exited at the first opportunity.

It wasn’t as straightforward as her record in Australia suggests. Sabalenka had to battle past Mirra Andreeva in the semis in a tougher match than the 6-3, 6-2 scoreline suggests, before overcoming a wobbly first set to beat qualifier Polina Kudermetova 4-6, 6-3, 6-2 in the final. Sabalenka hit 36 unforced errors in what was a pretty scratchy performance, but she got the job done.

At this stage, she knows that against pretty much every opponent, the match will be on her racket. If Sabalenka plays close to her best level, she appears pretty much unbeatable on this surface, with the rest of the field hoping for either a lights-out performance of their own, or one of Sabalenka’s increasingly infrequent off-days.

GO DEEPER

‘I can be the best player in the world’: Aryna Sabalenka crowns the season of her life

Charlie Eccleshare

Why so many injury retirements just a week into the season?

The first week of the 2025 tennis season — a chunk of which took place in 2024 — had a very 2021 feel, as Reilly Opelka and Naomi Osaka plowed into the finals in Australia and New Zealand respectively. Back then, Osaka was the world’s dominant woman and Opelka was a top-20 player.

But come the clinch, their starts to 2025 ended up feeling like their 2024s. Opelka, who has struggled with hip and wrist injuries and a host of related complications for much of the past two years, retired from his final in Brisbane against Jiri Lehecka with a back injury down 4-1 in the first set.

Osaka, who battled plenty of niggles through 2024 and ended the season early with a back injury, won the first set of her final against Clara Tauson before retiring with an abdominal injury.

It’s not the way either player wanted to finish some of their best weeks in a long time, but with the season’s first Grand Slam just six days away, stopping short of the finish line appeared to be the only safe move. One word they both used during their post-match comments: “Sorry”.

Both players have seemingly been around forever but are also still relatively young. Osaka, 27, said last year she was focused on trying to play at least another five to seven years; in Auckland she suggested that her longevity would be more tied to her ranking than her body.

“I’d rather spend time with my daughter if I’m not where I think I should be and where I feel like I can be,” she said in a news conference.

Opelka has not had the luxury of thinking long-term like that. A nearly seven-feet tall frame carries its own disadvantages when it comes to injury prevention.

Reilly Opelka beat Novak Djokovic on his run to the final in Brisbane (William West / AFP via Getty Images)

“I’m going to really embrace these next couple weeks to train and get a lot stronger physically,” Opelka said after his first-round loss at the U.S. Open in August, which was early days for his comeback.

“The goal is to be able to pin a really big offseason in December.”

There was one other high-profile retirement, with Tomas Machac suddenly pulling out of his match against Taylor Fritz in the semifinals of the United Cup. Machac, who was up a set and 5-2, had two match points on Fritz’s serve and served for the match, but the American broke him to take the set to 4-5.

At the changeover, Machac imploded, throwing his racket and screaming at his coach. At the next one, down 6-5 with Fritz serving to take the match to a third set, he did it again. One point into the game, Machac walked to the net and told Fritz he’d been suffering from cramps, having been pointing and gesturing at his upper legs for parts of the second set.

Machac then pulled out of the Adelaide International with a knee injury, also hoping to be fit for the Australian Open. Having spent 2024 looking at times like a world-beater, at times mentally and physically undercooked, he remains an enigma.

Matt Futterman

A last flourish for Kei Nishikori?

On the subject of injuries, given the rotten luck he’s had, surely no one would begrudge Kei Nishikori a last flourish in his career. Now 35, the former world No. 4 knows his best days are behind him, but continues to give everything in search of another big moment.

Just staying fit for a while would probably feel like enough, but Nishikori is suggesting he might just be capable of a first title in six years. He went all the way to the final in the 250-level Hong Kong Open last week, coming within a set of victory only to run out of steam in the final against Alexandre Muller, who won all five of his matches from a set down. Nishikori succumbed 2-6, 6-1, 6-3.

His resurgence follows his 2014 U.S. Open final opponent Marin Cilic coming back from devastating injury problems of his own to win the Hangzhou Open in September, and a month earlier Nishikori told The Athletic in a Zoom interview that 2025 was the year he wanted to push for better results.

Of 2024, he said, “I still want to go slow. And hopefully I can stay healthy and play many matches.” He then added, “I hope I can start playing good from next year.”

Most of the tennis world hopes so too.

GO DEEPER

How Marin Cilic and Kei Nishikori stunned tennis at the 2014 U.S. Open

Charlie Eccleshare

To defend or not to defend a title?

A strange thing happened during this Australian summer of tennis: the defending WTA champions of 2024 decided they didn’t much feel like protecting their titles.

Coco Gauff won Auckland last year; she played United Cup this year. Elena Rybakina won Brisbane; she, too decided to play the United Cup.

Emma Navarro won Hobart, back when she was a player who played tournaments the week before a Grand Slam because everything was new and she needed rankings points wherever she could find them. That’s not who she thought she was anymore, given that she is the world No. 8. She signed up for Brisbane, but then became one of a slew of seeds to exit early, falling to Kimberly Birrell of Australia.

That loss turned Navarro back into a player who plays the week before a Slam, with the American heading to Adelaide for matches moreso than points. Things worked out better for Gauff: she played five United Cup matches and won all five, the last against Iga Swiatek of Poland, her longtime nemesis. That’s about the definition of match-ready.

GO DEEPER

How does Coco Gauff solve a problem like Iga Swiatek?

Matt Futterman

Shot of the week

Coco Gauff has tennis fans digging out their protractors with this one.

Recommended reading:

🏆 The winners of the week

🎾 United Cup:

🏆 USA def. Poland 2-0 to win the United Cup in Sydney. It is the country’s second United Cup title.

🎾 ATP: 

🏆 Jiri Lehecka def. Reilly Opelka 4-1 (ret.) to win the Brisbane International (250) in Brisbane, Australia. It is his second ATP Tour title, both coming in Australia.
🏆 Alexandre Muller def. Kei Nishikori (WC) 2-6, 6-1, 6-3 to win the Hong Kong Open (250) in Hong Kong, China. It is his first ATP Tour title.
🏆 Joao Fonseca def. Ethan Quinn 6-4, 6-4 to win the Canberra International (Challenger 125) in Canberra, Australia. It is his second ATP Challenger title.

🎾 WTA:

🏆 Aryna Sabalenka (1) def. Polina Kudermetova (Q) 4-6, 6-3, 6-2 to win the Brisbane International (500) in Brisbane, Australia. It is her 18th WTA Tour title.
🏆 Claura Tauson (5) def. Naomi Osaka (7) 4-6 (ret.) to win the ASB Classic (250) in Auckland, New Zealand. It is the Dane’s third WTA Tour title.
🏆 Aoi Ito (7) def. Wei Sijia 6-4, 6-3 to win the Canberra International (WTA 125) in Canberra, Australia. It is her first WTA 125 title.

📈📉 On the rise / Down the line

📈 Mirra Andreeva moves up one place to a new career high of No. 15 after her run to the Brisbane International semifinals.
📈 Joao Fonseca ascends 32 spots from No. 145 to a new career high of No. 113 after winning the Canberra International.
📈 Polina Kudermetova moves up 50 places to a new career high of No. 57 after her run to the Brisbane International final.

📉 Andrey Rublev falls one place from No. 8 to No. 9, losing a key seeding slot for the Australian Open.
📉 Clara Burel drops four places from No. 99 to No. 103 to leave the top 100.
📉 Adrian Mannarino tumbles seven spots from No. 66 to No. 73 to drop out of the top 70.

📅 Coming up

🎾 ATP 

📍Adelaide, Australia: Adelaide International (250) featuring Tommy Paul, Felix Auger-Aliassime, Sebastian Korda, Denis Shapovalov.
📍Auckland, New Zealand: ASB Classic (250) featuring Ben Shelton, Giovanni Mpetshi Perricard, Gael Monfils, Jakub Mensik.
📍Melbourne, Australia: Australian Open Qualifying featuring Joao Fonseca, Alexander Blockx, Learner Tien, Cruz Hewitt.

📺 UK: Sky Sports; U.S.: Tennis Channel 💻 Tennis TV

🎾 WTA

📍Adelaide, Australia: Adelaide International (500) featuring Jessica Pegula, Donna Vekic, Ons Jabeur, Emma Navarro.
📍Hobart, Australia: Hobart International (250) featuring Dayana Yastremska, Rebecca Sramkova, Maya Joint, Sofia Kenin.
📍Melbourne, Australia: Australian Open Qualifying featuring Alycia Parks, Aoi Ito, Polina Kudermetova, Eva Lys.

📺 UK: Sky Sports; U.S.: Tennis Channel

Tell us what you noticed this week in the comments below as the men’s and women’s tours continue.

(Top photo: Getty Images; design: Eamonn Dalton)