Melbourne: 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.

‘Future top 10 player’

Federer hailed Chung as a future top 10 player after the South Korean’s campaign came to a painful end at the hands of the Swiss maestro.

In 20 years at the top, Federer has seen plenty of players come and go and only had praise for the youngster.

“I think he is already a great player, but we are talking next level excellence and I think he will achieve that,” said Federer, who is into his 30th Grand Slam final as he chases a 20th major title.

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

He added that he did not want to put too much pressure and expectation on Chung as “I don’t think it’s fair”.

But he said: “I think he’s going to have a lot of success. At what stage, how much, we will see.”

Chung’s unexpected run to be the first South Korean in a Grand Slam semi-final has drawn new fans to the sport in his homeland where tennis lags far behind golf and baseball in the popularity stakes.

Agencies