Sinner, Swiatek, teen sensation Fonseca top bill in Australian Open

MELBOURNE, Australia — Jannik Sinner steps up the defense of his Australian Open crown in the second round on Thursday in Melbourne, where Iga Swiatek, Daniil Medvedev and teenage rising star Joao Fonseca are all also in action.

Italian World No. 1 Sinner won his first-round match in straight sets and will hope for another quick victory when he takes on Australian wildcard Tristan Schoolkate in the night session on Rod Laver Arena.

By contrast, Russian firebrand Medvedev seems to like winning the hard way.

Four of his seven matches in Melbourne went the full distance a year ago, including his defeat in the final to Sinner.

And he needed another marathon to beat the 418th-ranked Kasidit Samrej on Tuesday in the first Grand Slam of the year.

Fifth seed Medvedev was 3-5 behind and on the brink of going two sets to one down against the Thai player when he saw red, slamming his racquet into the net camera repeatedly until they were both in bits.

Medvedev, who has lost three of the last four finals at Melbourne Park, faces the up-and-coming American Learner Tien, 19, who lost in the NextGen final to Fonseca.

The Brazilian sensation Fonseca has been tipped for the top after stunning ninth seed Andrey Rublev in straight sets in the first round.

"What can I say about it? Just incredible," four-time Grand Slam champion Carlos Alcaraz said.

The 18-year-old Fonseca faces unseeded Italian Lorenzo Sonego for a place in the third round.

Australian number one Alex de Minaur has an afternoon appointment against American Tristan Boyer on Rod Laver.

In the women's draw Poland's World No. 2 Swiatek opens the day session on Rod Laver Arena against Slovakia's Rebecca Sramkova.

Jasmine Paolini, Elena Rybakina, Emma Navarro and Emma Raducanu will also all look to book their places in the last 32.

Swiatek had a comfortable win first up against Katerina Siniakova and can regain the World No. 1 spot should top seed and defending champion Aryna Sabalenka suffer an early exit.

Paolini underlined her title credentials with an almost flawless march into the second round.

The 29-year-old Italian inflicted a dreaded first set 6-0 'bagel' on Chinese qualifier Wei Sijia.

The number four seed faces Renata Zarazua of Mexico to round off the night on Rod Laver Arena.

Sixth seed Rybakina blew away 16-year-old Emerson Jones in her opening match and faces American wild card Iva Jovic.

Navarro, seeded eight, reached the quarterfinals and semifinals, respectively, at Wimbledon and the US Open last year.

She has a last-64 clash with China's 108th-ranked Wang Xiyu.

The 2021 US Open champion Raducanu, of Britain, faces Amanda Anisimova of the United States in a first clash between the friends.

The leading seeds will be attempting to avoid the same fate as fifth seed Zheng Qinwen, China's Olympic champion, who was dumped out in the second round on Wednesday.

It was the biggest upset of the tournament so far.