Serena Williams of the United States celebrates during her second round match against Tamara Zidansek of Slovakia on day three of the 2020 Australian Open at Melbourne Park in Melbourne, Australia, January 22, 2020.
Fifteen-year-old prodigy Coco Gauff set up an Australian Open blockbuster with defending champion Naomi Osaka on Wednesday, as a pumped-up Serena Williams took another step towards a record-equaling 24th Grand Slam title.
On a day when men's seeds tumbled, Serbia's Novak Djokovic strode into the third round to be joined by Roger Federer, who dismissed Filip Krajinovic 6-1, 6-4, 6-1.
American teenager Gauff, showing a tenacity which is becoming her trademark, clawed her way back from a set down to beat the experienced Sorana Cirstea 4-6, 6-3, 7-5.
Gauff, who screamed and pumped her fists as she completed her victory, said her "will to win" had got her through the tough second-round match at a windswept Melbourne Park.
"My parents always told me you can always come back – no matter what the score is," said Gauff, who beat seven-time Grand Slam champion Venus Williams in round one.
Coco Gauff of the United States plays a backhand in her second round match against Sorana Cirstea of Romania on day three of the 2020 Australian Open, Australia, January 22, 2020.
Gauff also beat Williams on her Grand Slam debut last year at Wimbledon, and in another quirk, she faced Osaka in the U.S. Open third round, going down meekly in straight sets.
Japan's Osaka, 22, beat China's Zheng Saisai 6-2, 6-4 but briefly lost her cool mid-match, hurling and kicking her racket when she gave up a break in the second set.
"I was thinking that I really don't want to play a third set this time," explained Osaka, who is defending a Grand Slam title for the second time.
Naomi Osaka of Japan plays a shot during the second round of the 2020 Australian Open, January 22, 2020.
Former world number one Wozniacki, playing her final tournament before retiring, came from behind in both sets for a 7-5, 7-5 win over Dayana Yastremska of Ukraine.
Serena Williams shouted at the top of her voice during a testing second set against 70th-ranked Tamara Zidansek, before seeing off break points to win 6-2, 6-3.
"She was a really good fighter – she did not just let me win," said Williams, who can equal Margaret Court's all-time mark of 24 Grand Slams if she lifts the trophy.
Wind 'massive factor'
Earlier, Australia's world number one Ashleigh Barty raced through 6-1, 6-4 against Polona Hercog, buoying hopes of a first home winner since 1978.
"It was very different end to end, I think the wind was a massive factor particularly with the new ball," she said.
Djokovic also weathered the breeze – which followed heavy rain on Monday, and smog from bushfires last week – to beat Japanese wildcard Tatsuma Ito 6-1, 6-4, 6-2 in 95 minutes.
"They were tough conditions, pretty windy and it was hard to know where the balls were going. My serve helped a lot to get me out of trouble," said the Serb.
Federer was barely detained by Krajinovic, the world number 41, as he moved smoothly through in 92 minutes in the night match on Rod Laver Arena.
Roger Federer of Switzerland plays a backhand during his Men's Singles second round match against Filip Krajinovic of Serbia on day three of the 2020 Australian Open, January 22, 2020.
"Very happy, been a great start to the season," he said as he moved a step closer to a 21st Grand Slam title. "I feel really relaxed on court. I've trained hard and you always hope it pays off."
Over his two matches so far, Federer has dropped just 13 games, and admitted he preferred easy early encounters rather than tough battles to preserve energy.
"I prefer this much more than overcooked. As easy as it looks, there's always the effort, trying to extend the lead," he said.
"Of course, it's not quite the same stress level if you're down a set or a break or two sets, whatever it may be. I prefer it this way because you have always extra left in the tank if you need it."
He faces a tougher assignment next against Australian John Millman, who beat him in four tough sets at the 2018 U.S. Open.
"He's fit like a fiddle. I've lost to him in the past... he's from this country so naturally also it's going to be different intensity. I think this is going to be a good test for me."