Top seed Simona Halep set up a highly anticipated Australian Open last-16 tie against Serena Williams by beating the American’s older sister Venus.

The 27-year-old Romanian eased to a 6-2 6-3 victory, winning in straight sets for the first time at this year’s tournament in Melbourne.

Seven-time champion Williams, 37, reached the last 16 by thrashing 18-year-old Ukrainian Dayana Yastremska.

“It’s going to be a bigger challenge but I’m ready to face it,” said Halep.

The Romanian says she has “nothing to lose” against the 23-time Grand Slam champion, who is aiming to match Australian Margaret Court’s all-time record of major triumphs.

Williams has won eight of their nine previous matches, with their last meeting coming at the US Open in 2016.

Since then, Halep has won her first Grand Slam title, having triumphed at last year’s French Open.

• Williams comforts teenager after victory
• Djokovic’s dark mood over lights overshadows win
• Osaka and Svitolina fight back to win

Halep puts herself among the contenders

Halep, who lost to Caroline Wozniacki in last year’s final, said she came into the first Grand Slam of the year with “no expectations” after a difficult past five months.

She arrived in Melbourne having not won since August, a five-match losing streak punctured by an absence with a back injury, while she also split with her long-time coach Darren Cahill in November.

After needing her fighting qualities to beat Estonian veteran Kaia Kanepi and young American Sofia Kenin in the opening two rounds, Halep moved up a level against seven-time major winner Williams, 38.

“It was a great match – my best match here this year,” Halep said.

“It is always a big challenge to play against the Williams sisters so I was super motivated.”

Halep could not take any of three break points in Williams’ first two service games, yet was finally rewarded in the fifth game to lead 3-2.

After surviving four break points in the next game, Halep took control of the opener as Williams appeared to wane physically in a set containing some lengthy rallies.

The points became shorter at the start of the second, allowing Williams to stick with Halep as they stayed on serve to 3-3.

But when Williams failed to land a first serve in the seventh game, Halep pounced.

Two break points – added to the five she created in the first set – arrived and she upped the pace to force Williams into sending a weak backhand into the net on the first.

Serving to stay in the match, Williams produced two double faults to hand Halep two match points – but the Romanian only needed one and sealed victory with a stunning forehand down the line.

• Live scores, schedule and results
• Follow the Australian Open on BBC TV, radio and online
• Alerts: Get tennis news sent to your phone

Seven-time champion Serena Williams comforted opponent Dayana Yastremska after powering past the teenager into the Australian Open fourth round.

Williams beat the 18-year-old Ukrainian 6-2 6-1 in one hour and seven minutes and did not drop a service game.

“You’re gonna make it, don’t cry”, Williams, 37, told a tearful Yastremska following her victory.

The American will face Romanian world number one Simona Halep or sister Venus Williams in the next round.

“I thought she did really amazing,” Williams said when asked about the future of Yastremska, who was not even born when the American won the first of her 23 Grand Slam singles titles in 1999.

“She came out swinging and to be so young, she came out ready to go. When I was young I played against so many people and everyone I faced was intimidating and not easy. You just go out and swing and do the best you can.”

• Live scores, schedule and results
• Follow the Australian Open on BBC TV, radio and online
• Alerts: Get tennis news sent to your phone

Williams in the driving seat

Williams is favourite to win a record-equalling 24th Grand Slam singles title in Melbourne and her performance in the third round showed why.

She put youngster Yastremska under immediate pressure, breaking in the first game and winning four games in a row.

The occasion seemed to have got the better of the Ukrainian – a promising talent who could only provide brief glimpses of her ability and could not hide inconsistencies with her serve.

But Williams was ruthless and looks firmly on course to win a record-extending eighth Australian Open title.

With defending champion Caroline Wozniacki exiting on Friday and rivals Naomi Osaka – the fourth seed – and Elina Svitolina – the sixth seed – being forced to fight back to scrape their way into the fourth round, it is so far falling into place for Williams.

Her toughest test yet will be in the next round where a mouth-watering tie with either Halep or her elder sister awaits.

Williams joked that sister Venus “still intimidates me now” but that she is enjoying being back in Melbourne after missing last year’s competition four months after she gave birth.

Roger Federer delivered a serving masterclass to sweep aside American Taylor Fritz and reach the Australian Open fourth round.

The defending champion won 6-2 7-5 6-2 under the roof on Rod Laver Arena at a rainy Melbourne Park.

The Swiss third seed, 37, is aiming to become the first man to win seven Australian Open titles.

Next up for him is Greek 14th seed Stefanos Tsitsipas, who beat Nikoloz Basilashvili 6-3 3-6 7-6 (9-7) 6-4.

Joining Federer in the next round is Czech former semi-finalist Tomas Berdych, who knocked out Argentine 16th seed Diego Schwartzman 5-7 6-3 7-5 6-4.

Unseeded Berdych, who beat Britain’s Kyle Edmund in the first round and has found his form after an injury-hit 2018, will play the winner of Friday’s match between world number two Rafael Nadal and Australian Alex de Minaur.

• Nadal sees off Australian hope De Minaur
• Sharapova knocks out champion Wozniacki
• Teenager Anisimova beats seed Sabalenka

Federer serves up victory in style

The Swiss was in a ruthless mood from the start, breaking Fritz’s second and third service games on his way to a 5-1 lead.

But it was on his own serve where the 20-time Grand Slam champion dominated, with Fritz taking just two points on the Federer serve in the first set.

He sealed the set with an ace with just 20 minutes on the clock and carried on where he left off in the second with back-to-back holds to love.

But the 21-year-old American began to apply a bit more pressure on Federer’s serve midway through the second, taking him to deuce in the eighth game before losing his own serve three games later.

From there Federer served for the set, once again wrapping it up with an ace – the eighth of his 10.

Back-to-back breaks in the third sealed the fate of Fritz, who had shown glimpses of a promising future with his shot-making as well as an ability to laugh at himself when he fluffed an easy smash.

“I wanted to get out the blocks quickly as I knew of the threat and his possibilities on the serve,” said Federer, who was playing his 100th match on the Rod Laver Arena.

“The second set was tough. There were a few chances but he protected his serve well and it was close. We had some good points and it was fun. I wish him all the best for the future.”

• Live scores, schedule and results
• Follow the Australian Open on BBC TV, radio and online
• Alerts: Get tennis news sent to your phone

Cilic scrapes through into last 16

Sixth seed Marin Cilic saved two match points on his way to a five-set victory over 2009 semi-finalist Fernando Verdasco.

The Croat, beaten in last year’s final by Roger Federer, fought back from two sets down to win 4-6 3-6 6-1 7-6 (10-8) 6-3 in a match that lasted four hours 18 minutes and finished at 12.57am local time.

In the fourth set tiebreak Cilic saved one match point with a huge serve into the corner before Verdasco double faulted on the second match point, hitting the net cord with his second serve.

“It was definitely a tough tiebreak,” said Cilic. “It came down to one shot, or basically one decision. I was a little bit lucky on that net cord. I was just slightly luckier in those crucial moments.

“It was definitely a tough match, unbelievable.”

Murray conqueror Bautista Agut into another Grand Slam last 16

Cilic will next play Roberto Bautista Agut, who beat Andy Murray in the first round in what may have been the Briton’s final match.

The Spaniard, seeded 22nd, knocked out 10th seed Karen Khachanov of Russia 6-4 7-5 6-4.

It is the fourth time Bautista Agut has made the fourth round of the Australian Open, but he has never made it past the last 16 in a Grand Slam, losing at that stage on 10 occasions.

Elsewhere, 2017 semi-finalist Grigor Dimitrov also won, with the Bulgarian beating Italian Thomas Fabbiano 7-6 (7-5) 6-4 6-4.

Up next for Dimitrov is 20-year-old American Frances Tiafoe, who will be playing in the fourth round of a Grand Slam for the first time in his career.

Tiafoe eliminated fifth seed Kevin Anderson on Wednesday in round two and fought back from two sets to one down on Friday to defeat Italy’s Andreas Seppi 6-7 (3-7) 6-3 4-6 6-4 6-3.