Defending champion Roger Federer eased into his seventh Australian Open final in a bitter-sweet win after South Korean young gun Chung Hyeon retired injured in their last four showdown Friday. 

The Swiss great was leading 6-1, 5-2 when Chung called it quits with foot blisters, and he will now face Marin Cilic in his 30th Grand Slam final on Sunday. 

Chung, the first South Korean man or woman to play in a semi-final at one of the four majors, was treated in a medical timeout for the left foot problem just two games earlier. 

But it came as a big surprise when the 21-year-old walked to the net at 30-30 and trailing 2-5 after 62 minutes in the second set to throw in the towel. 

It pitched Federer into his seventh Australian final as he chases his sixth Melbourne title and a record 20th Grand Slam victory. 

He leads 2014 US Open champion Cilic 8-1 in their meetings. 

“This feels bitter-sweet. Obviously I'm incredibly happy to be in the finals, but not like this,” Federer said of the abrupt ending. 

“I would have preferred a normal end, yes. But I must admit, as well, you do take the faster matches whenever you can. 

“There's enough wear and tear on the body, there's enough tough matches throughout the season that when they happen, you take them. 

“There's nothing you can do anyway about it. I'm just happy I'm in the final, to be honest.”

The Swiss maestro now has a 30-13 win-loss record in Grand Slam semi-finals and has yet to drop a set in this year's Australian Open. 

“You couldn't tell until the end,” he said of Chung's injury problems. “That's probably why a lot of people are stunned (he retired). 

“I could tell something was wrong before he took the injury timeout, but he has a great composure. 

“I think he is already a great player, but we are talking next level excellence and I think he will achieve that. 

“We will see much more of him. Top 10 for sure. The rest we will see.”

It was a muted semi-final with the retractable roof closed on Rod Laver Arena for rain, further improving Federer's chances given his strong indoor record. 

He broke Chung's opening service and twice more to romp away with the first set in just 33 minutes as the Korean made a flurry of errors. 

It got no better in the second set with Federer again breaking in the fourth game before the trainer was called on to the court to treat Chung for his foot blisters. 

Chung only lasted a bit more than two games before pulling out to a stunned silence. 

“It's like worse than regular blisters. Over the last few days, it was blister under blister under blister,” said Chung at his post-match press conference. 

“Now it's red raw.” He added that retiring was the “right thing”. 

“If I play bad on the court, it's not good for the fans and audience as well,” he said. 
Federer was sympathetic. 

“I've played with blisters in the past a lot, and it hurts a lot, and at one point it is just too much and you can't take it anymore,” he said. 

“That's when you realise there is no way you can come back and you make things really worse, it is better to stop.”

Federer broke Chung's serve four times off 11 break points and only had one break point on his own service. 

The Swiss second seed hit 24 winners while Chung made 17 unforced errors in 14 games, eight of them off his normally potent forehand which Federer targeted.

DAY ELEVEN REPORT: Federer faces Chung semi test as Kerber and Halep shine

DAY NINE REPORT: Cilic into Open semis as injured Nadal retires

DAY SEVEN REPORT: Relieved Rafa survives test as Dimitrov ousts Kyrgios

Rafael Nadal battled through a huge test to make his 10th Australian Open quarter-final Sunday as Grigor Dimitrov ousted Nick Kyrgios to join him and Caroline Wozniacki kicked into full gear. 

On an overcast and muggy day at Melbourne Park, the Spanish world number one was up against his most dangerous opponent yet in pocket-rocket Diego Schwartzman, one of the smallest men on tour. 

The Argentine 24th seed endeared with his astonishingly powerful groundstrokes before Nadal prevailed 6-3, 6-7 (4/7), 6-3, 6-3 in almost four hours on Rod Laver Arena. 

It kept alive his push for a 17th Grand Slam title and also ensured he will remain number one when the new rankings come out after the tournament. 

“It was a great battle,” said Nadal, who is chasing his second Melbourne title after beating Roger Federer in the 2009 final. 

“Of course, I feel little bit tired, but I was able to keep fighting until the end.”

He will play sixth seed Marin Cilic for a place in the semi-finals after the Croat beat Spanish 10th seed Pablo Correna Busta 6-7 (2/7), 6-3, 7-6 (7/0), 7-6 (7/3). 

The win was Cilic's 100th at a Grand Slam. 

“I have played great tennis from the first round against tough opponents and now I am really looking to the next match, it will be definitely be a big challenge,” he said of the Nadal clash. 

Ordinarily Nadal, as the top seed, would have top billing on Rod Laver in the evening, but not with local star Kyrgios in action. 

The maturing Australian 22-year-old pushed world number three Dimitrov close in a hugely entertaining four setter before succumbing 7-6 (7/3), 7-6 (7/4), 4-6, 7-6 (7/4). 

“Playing Nick is always tricky,” said the Bulgarian, as he targets bettering the semi-finals he made last year. 

“It was one of those matches you had to take any opportunity that you got.” His reward is a showdown with Briton Kyle Edmund, who reached his first Grand Slam quarter-final with a 6-7 (4/7), 7-5, 6-2, 6-3 win over Italy's Andreas Seppi. 

World number two Wozniacki turned on the style in her match to take another step towards a maiden Grand Slam title. 

The assured Wozniacki, a semi-finalist in 2011 who has never quite lived up to the hype in the majors, annihilated 19th-seeded Magdalena Rybarikova 6-3, 6-0 in her most impressive performance to date. 

“She really mixes up the pace, I just tried to calm down, get my returns in and wait for the opportunities to attack,” she said after crushing the Slovak, who made the semi-finals at Wimbledon last year. 

“I think you can tell my confidence is pretty good at the moment.” Her easy passage sets up a last-eight clash with gritty Spaniard Suarez Navarro, who battled back from a set and 4-1 down to shatter the hopes of 32nd seed Anett Kontaviet. 

The Estonian had been bubbling with confidence after despatching French Open champion Jelena Ostapenko in the third round, but nerves got the better of her. 

The Spaniard, who has made the quarter-finals in Melbourne twice before, most recently in 2016, credited her fightback with a conscious decision to be more aggressive. 

“My team all the time they say (to) me, play aggressive, play aggressive. That's I think what I did,” said Suarez Navarro, one of the few who still uses a one-handed backhand. 

Looking ahead to Wozniacki, she added: “I know how she plays. I know how tough she is. It will be a really interesting match.” The 37th-ranked Elise Mertens also made the last eight, becoming the first Belgian since Kim Clijsters in 2012 to get so far in Australia. 

She posted a straight-sets win over Croat Petra Martic and will now play either fourth seed Elina Svitolina or Czech qualifier Denisa Allertova.

DAY SIX REPORT: FedExpress steams on as Sharapova grinds to halt

Roger Federer and Novak Djokovic kept up their relentless march towards a semi-final meeting at the Australian Open Saturday as Maria Sharapova suffered a crushing defeat by Angelique Kerber. 

The two greats of the game -- who have won 11 Australian Opens between them -- could meet in the last four if they maintain their winning ways. 

Defending champion Federer was never troubled by France's Richard Gasquet, who has failed to take a set off him since 2011, as he steamed into the last 16 with a 6-2, 7-5, 6-4 win. 

“The second set was tight, the match was close and I had to focus to the very end,” said the Swiss 19-time Grand Slam winner, who next plays little-known Hungarian Marton Fucsovics for a place in the quarter-finals. 

He added: “So far, so good.” Djokovic was equally convincing in his 6-2, 6-3, 6-3 rout of Spanish 21st seed Albert Ramos-Vinolas, although there was concern when he sought a medical timeout for treatment to his lower back. 

“It was straight sets but I had to earn my points,” insisted the Serb, who is on his way back after six months out with right elbow trouble. 

“Obviously for me it's taking it one match at a time but I have to be more humble with my expectations as I haven't played in the last six months.” He next plays South Korea's Chung Hyeon, who shocked fourth seed Alexander Zverev. 

With the temperatures a manageable 26 Celsius (79 Farenheit) at Melbourne Park after two days of oven-like conditions, Zverev was beaten in five sets. 

He has been hailed as the leader of the tennis new guard but has now failed to go beyond the fourth round in 11 Grand Slams, admitting he has “some figuring out to do”. 

In a glamour evening tie, Sharapova was no match for Kerber, flopping 6-1, 6-3. 

They pair are both 30, former world number ones and were the only two Australian Open winners left in the women's draw, but there was only one player in it. 

“This court is special for me and I was trying to enjoy every point,” Kerber said of Rod Laver Arena, where she beat Serena Williams in the 2016 final. 

Kerber is in scintillating form, having won the lead-up Sydney International, and will face Taiwan's Hsieh Su-wei for a place in the quarter-finals. 

For Sharapova, who is looking to rediscover her best on her way back from a 15-month drugs ban, it is back to the drawing board. 

“I think there are a lot of things that I need to get better at and improve on,” she admitted. 

World number one Simona Halep is lucky to be still in contention after surviving three match points in a titanic struggle against 76th-ranked American Lauren Davis. 

She looked out for the count at one point but finally got over the line 4-6, 6-4, 15-13 in a gruelling 3hr 44min epic that took its toll. 

“I'm almost dead,” the tenacious Romanian said after the incredible battle, in which Davis lost a toenail and Halep served for the match four times. 

The former quarter-finalist will now play Naomi Osaka after the Japanese star beat Australia's Ashleigh Barty. 

Sixth seed Karolina Pliskova also had a tough test, beating fellow Czech Lucie Safarova 7-6 (8/6), 7-5. 

In contrast, US Open finalist Madison Keys was in fine touch as she benefits from the guidance of former great Lindsay Davenport. 

Flying under the radar, the 17th seed has surrendered just 16 games on her way to the fourth round after beating Romania's Ana Bogdan 6-3, 6-4. 

She will next face French eighth seed Caroline Garcia, who was too strong for Belarussian Alaksandra Sasnovich. 

Among the men through was Austrian fifth seed Dominic Thiem and veteran Tomas Berdych, along with American Tennys Sandgren, who had never won a Grand Slam match before this year's Australian Open.

DAY FIVE REPORT: Confident Nadal demolishes Dzumhur

DAY THREE: Nadal dominant as big guns pull off great escapes

Rafael Nadal swept into the Australian Open third round to keep his Grand Slam title hunt on track Wednesday, as Caroline Wozniacki and Grigor Dimitrov pulled off great escapes to stay in contention. 

The world number one Spaniard's march towards a 17th Grand Slam crown was never threatened by Argentina's Leonardo Mayer, who took him to a third set tiebreak before being swatted aside 6-3, 6-4, 7-6 (7/4) on Rod Laver Arena. 

“Playing this court is always a big motivation for me,” said Nadal, who lost last year's final to Roger Federer. 

“He was a dangerous opponent and I'm happy to be in the third round. 

“For my team and my family, this is our favourite tournament of the year, so I hope to stay around a bit longer,” he added. 

Nadal, showing no signs of the troublesome knee that bothered him late last season and interrupted his Melbourne lead-up, next plays Bosnian 28th seed Damir Dzumhur. 

Surprisingly, he was not the prime time men's night match on centre court, with that honour going to third seed Dimitrov, who survived a huge scare from unheralded qualifier Mackenzie McDonald. 

The Bulgarian needed to call on all his experience to down the 186th-ranked American 4-6, 6-2, 6-4, 0-6, 8-6. 

“I'm very happy with the win, not because the way I played, but because the way I fought,” said Dimitrov. “It all came down to a few points here and there.” In contrast to Nadal's easy progress, world number two Wozniacki also struggled against little-known Croat Jana Fett. 

The Dane saved two match points and rallied from 5-1 down in an epic third set to keep her dream of a first Grand Slam title alive. 

She looked out for the count, and was struggling afterwards to work out how she survived 3-6, 6-2, 7-5 against a player ranked 119. 

“That was crazy, I don't how I got back in the match,” said Wozniacki, adding that “experience was crucial”. 

Fourth seed Elina Svitolina also came from a set down to overcome spirited Czech Katerina Siniakova 4-6, 6-2, 6-1. 
The Ukrainian is now on a seven-match win streak and after picking up five WTA Tour titles last year, more than any other woman, is a serious Grand Slam contender. 

Her next task is tackling 15-year-old sensation Marta Kostyuk, who became the youngest woman to reach the third round since Martina Hingis got to the quarter-finals in 1996. 

Also Ukrainian, she beat local wildcard Olivia Rogowska 6-3, 7-5. 

Her win streak at Melbourne Park is now 11 straight matches after claiming the Australian Open girls' title in 2017 and coming through qualifying this year. 

“I heard a lot of times that I'm talented, and I know that,” said the confident teen. “But I know that only talent will not help me to play good. So I'm working pretty hard.”

Svitolina said she knew little about the youngster, and was preparing for a no-holds barred fight. 

“She has nothing to lose, so that's why I know she goes just for everything. You know, a little bit like a headless chicken,” she said. 

French Open champion and seventh seed Jelena Ostapenko also progressed, but she too needed three sets to get past China's Duan Yingying. 

On a hot Melbourne day, Croatia's sixth seed Marin Cilic advanced, with last year's Wimbledon finalist easily beating Joao Sousa. 

US Open semi-finalist and 10th seed Pablo Carreno-Busta also went through after French veteran Gilles Simon retired injured when trailing 6-2, 3-0. 

And fighting former finalist Jo-Wilfried Tsonga saw off rising Canadian youngster Denis Shapovalov in a five-set thriller. 

But Russia's Anastasia Pavlyuchenkova, a quarter-finalist last year, became the latest seed to slump out in the women's draw, which has been shorn of leading names over the first two rounds. 

Venus Williams' conqueror Belinda Bencic also ran out of steam, having no answers against Thai qualifier Luksika Kumkhum, slumping out 6-1, 6-3.