Luciano Darderi makes an early statement, crunching a forehand winner for 0-15.

Jannik Sinner is struggling to find his radar on serve and with a big forehand return down the line off a tame second serve, Darderi has two break points.

Right, time to get this last-16 tie under way.

Luciano Darderi, the 22nd seed and a clay-court specialist enjoying a career-best run in Melbourne, won the coin toss and elected to receive, so Jannik Sinner will serve first.

Apparently the second seed has never lost to a fellow Italian on the ATP Tour, which doesn't bode well for Darderi.

However, Sinner struggled in the heat in round three, so it will be interesting to see how he's recovered and if anything changes in his approach to this match.

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Jannik Sinner admitted he "got lucky with the heat rule" in his third-round victory over world number 85 Eliot Spizzirri as he kept his quest for a third consecutive Australian Open crown alive.

The 24-year-old world number two had lost the opening set and was trailing 3-1 in the third and struggling to walk when the heat stress scale hit its maximum of five, forcing the umpire to call play to a halt.

Sinner recovered to win 4-6 6-3 6-4 6-4 having previously eased through matches against Hugo Gaston and James Duckworth.

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Luciano Darderi, one of eight Italians currently ranked inside the world top 100, has been on something of a hot-streak since the middle of 2025.

Having never previously progressed beyond the second round at a major, he made back-to-back third-round appearances at Wimbledon and the US Open ahead of his ongoing run to the Australian Open last 16.

This is only his second appearance in the main draw in Melbourne, exiting in the first round in 2025.

Darderi, the 22nd seed, defeated Christian Garin in three sets and Sebastian Baez in four before downing 15th seed Karen Khachanov 7-6 (7-5) 3-6 6-3 6-4.

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It's an all-Italian clash on Margaret Court Arena, with Jannik Sinner taking on Luciano Darderi.

Defending champion Sinner, the world number two, has reached at least the quarter-finals in his past eight Grand Slam appearances, including winning four titles and featuring in a further two finals.

By contrast, Darderi, the 22nd seed, is making his debut in the second week of a major.

This is the first meeting between the two players, with the winner facing either Ben Shelton or Casper Ruud in the last eight.

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You might have been expecting to see Novak Djokovic in action on day nine but the 24-time Grand Slam champion has received a walkover into the quarter-finals.

His opponent, Czech 16th seed Jakub Mensik, withdrew from the tournament on Sunday through injury.

In a statement, Mensik said: "This is a tough one to write. After doing everything we could to keep going, I have to withdraw from the Australian Open due to an abdominal muscle injury that has progressed over the last matches.

"After a long discussions with my team and doctors we decided not to step on court [on Monday].

"Even though I'm disappointed, making the fourth round here for the first time is something I will carry with me for a long time. I felt so much energy from the fans and the atmosphere in Melbourne was truly special."

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Defending women's champion Madison Keys is out of the Australian Open. The ninth seed lost to fellow American Jessica Pegula - the sixth seed - 6-3 6-4.

She will face fourth seed Amanda Anisimova, who beat Xinyu Wang in straight sets, in the last eight which guarantees there will be at least one American in the semi-finals.

Fifth seed Elena Rybakina is through to a Grand Slam quarter-final for the first time since Wimbledon in 2024 after beating Elise Mertens 6-1 6-3.

In the men's singles, fifth seed Lorenzo Musetti beat American ninth seed Taylor Fritz 6-2 7-5 6-4 to set up a quarter-final against 24-time Grand Slam champion Novak Djokovic.

It was a routine day for the top seeds on Sunday, with world number ones Carlos Alcaraz and Aryna Sabalenka cruising through to the quarter-finals.

Sabalenka overcame Canadian rising star Victoria Mboko, the 17th seed, in straight sets, setting an Open era record for the most consecutive tie-breaks won at Grand Slams in the process.

Her reward is a last-eight tie against another dangerous teenager - and Mboko's doubles partner - in Iva Jovic. The 18-year-old American, seeded 29th, dropped just one game in her win over Yulia Putintseva.

Alcaraz beat American 19th seed Tommy Paul 7-6 (8-6) 6-4 7-5 and will face Australian favourite Alex de Minaur on Tuesday after the sixth seed cruised to victory over Alexander Bublik, losing just six games.

Learner Tien, 20, produced a similarly emphatic performance to down 11th seed Daniil Medvedev and reach his first Grand Slam quarter-final. 2025 finalist Alexander Zverev came past Francisco Cerundolo in straight sets.

Women's third seed Coco Gauff proved too strong for Karolina Muchova, winning 6-1 3-6 6-3, while 12th seed Elina Svitolina comfortably beat teenage eighth seed Mirra Andreeva.

World number two and defending champion Jannik Sinner will be in action shortly on Margaret Court Arena against fellow Italian Luciano Darderi.

We'll be bringing you game-by-game coverage of that match right here.

Women's second seed Iga Swiatek will be on Rod Laver Arena from 08:00 GMT. She faces Australian qualifier Maddison Inglis.

That match will be followed by American eighth seed Ben Shelton against Norwegian 12th seed Casper Ruud.

Hello there. Happy Monday.

It's day nine of the Australian Open and time to wrap up the fourth round in the men's and women's singles.

Let's get cracking.

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