"It's nice to see the turnaround through the off-season, coming here, playing well".
Federer, who defeated Nadal in the Australian Open final a year ago, said it was hard to see the star's campaign at Melbourne Park end in that way.
His loss to Chung, whose unbelievable court coverage reminded those watching of Djokovic himself, wasn't fully unexpected.
Roger Federer with Tomas Berdych after his straight sets win in Melbourne. He hasn't lost to the Czech veteran since Dubai in 2013. The 21-year-old is now ranked 58th, with his career best coming last September at No. 44.
Men's action from Melbourne Park starts at 2am United Kingdom time, with Tennys Sandgren taking on Hyeon Chung in what could be described as an unlikely Grand Slam quarter-final. "It's fun. It's such a fun challenge because he does so many cool things with how he moves and how he returns and how he plays with his forehand", he said. Chung has won three of his last four semifinal matches, two of which came in challenger play. I know that I can win close matches and also, yeah, going out there and playing good in the bigger tournaments.
Given what he's accomplished on the courts at Melbourne Park, Sandgren's story was initially focused on his tennis. Her older sister, Venus Williams, was beaten in the first round.
"I tried to play a bit more aggressive, get some rhythm going, because Tomas found that early", he said.
A finalist at the U.S. Open in 2009 and 2014, Wozniacki needed three sets to beat Mertens on clay in a semifinal in Bastad, Sweden past year at their only previous meeting. "I have to think about the ceremony".
There were plenty of people who believed Djokovic, a six-time champion Down Under, could win another title here this year. She had dropped just 19 games - the fewest among the eight women's quarterfinalists. I like it when we don't know the guys.
Hyeon Chung's historic run through draw is continuing.
In a tense 11-minute final game he claimed victory on his sixth match point after Sandgren threw everything at the South Korean in a bid to stay in the match. He beat Mischa Zverev, an Australian quarterfinalist previous year, in the first round; Sydney International champion Daniil Medvedev in the second round; fourth-seeded Alexander Zverev in the third round; and six-time champion Novak Djokovic in the fourth round. He will next face Roger Federer in the semis on Friday. "He definitely has the game to be a top-10 player".
Andy Murray missed the tournament because of hip surgery, Stan Wawrinka and Novak Djokovic suffered early exits in their first appearances for six months because of knee and elbow injuries respectively, while Rafael Nadal retired hurt with a hip muscle problem in the fifth set of his quarter-final against Marin Cilic on Tuesday.
It's a different challenge for the 19-time grand slam victor but one he believes is good for the game. In fact, Nadal had an MRI on his leg and said the injury to his leg is not too serious and he should only be out for three weeks.
The No. 58-ranked Chung beat his childhood hero on Rod Laver Arena to secure a spot in a quarterfinal against No. 97-ranked Tennys Sandgren, who had never won a match at a major until last week.
Some of the fans headed toward the exits, but the players remained behind the baselines as chair umpire James Keothavong ed stadium staff to work out if it was a false alarm.