MELBOURNE, Jan. 20 (Xinhua) -- Chinese players Wu Yibing and Wang Xinyu reached the second round of the Australian Open after stirring victories, while Jannik Sinner and Madison Keys made successful starts to their title defenses on Tuesday.
Having rolled through the qualifying draw, Wu showcased his confident form by outlasting Italy's Luca Nardi to reach the second round of the Australian Open for the first time in his career.
Wu was rewarded for his aggressive play and he hit 45 winners to prevail 7-5, 4-6, 6-4, 6-2 in just under three hours.
The 26-year-old will next play Eliot Spizzirri, who upset 28th seed Joao Fonseca.
In the night session, Sinner started his quest for a third straight Australian Open title by comfortably winning the opening two sets before France's Hugo Gaston retired injured.
An ailing Gaston, world No.93, had to pull the pin just 68 minutes into the first round match after struggling to move around the center court of Rod Laver Arena.
Sinner, a four-time grand slam champion, hit 19 winners and led 6-2, 6-1 in his first match in over two months.
"Not the way you want to win the match but he's a very talented player," Sinner said. "I'm very happy to come here, it's a special place."
Americans Ben Shelton and Taylor Fritz also advanced.
In the women's draw, Wang underlined her status as China's highest-ranked player at this year's Australian Open after a 6-3, 6-3 victory over qualifier Anhelina Kalinina.
The world No.46 fired down 10 aces in her dominant 6-3, 6-3 first round victory in one hour and 33 minutes.
Wang will play former French Open champion Jelena Ostapenko in the second round.
But veteran compatriot Zhang Shuai fell short in a titanic three-set match to inspired Australian wildcard Taylah Preston.
The 20-year-old was in tears after hitting 26 winners in a breakout 6-3, 2-6, 6-3 victory in one hour and 33 minutes at a rowdy Kia Arena.
"I'm just really happy. I put in a lot of hard work, it's really nice," said 20-year-old Preston, who exacted revenge after losing to Zhang in three sets in Brisbane earlier in the month.
Earlier, Keys made a nervous start before sealing a 7-6 (6), 6-1 win over Ukraine's Oleksandra Oliynykova.
The ninth seed stepped onto the court of her famous upset in the final over world No.1 Aryna Sabalenka but struggled to reach those same heights in a sluggish launch of her title defense.
"I think at the start I just felt like I was playing just a little timid and not really trusting my first instinct," Keys said. "As nervous as I was at the start, I'm really glad to be back and to win that match."
Former tournament champion Naomi Osaka also made it through after battling past Antonia Ruzic in three sets.
In the women's doubles, China's Tang Qianhui and Maia Lumsden of Britain fell to Italians second seeds Jasmine Paolini and Sara Errani.
On Wednesday, Chinese qualifier Bai Zhouxuan will face Sabalenka in the second round while top seed Carlos Alcaraz headlines the men's draw.
Two-time grand slam champion Coco Gauff and last year's finalist Alexander Zverev are also in action on a day four that sees home hope Alex de Minaur fly the Australian flag. ■
