Dan Evans gave the tennis world a reminder of his considerable talents by pushing Roger Federer in a 7-6 (5) 7-6 (3) 6-3 defeat in the second round on Rod Laver Arena.
Katie Boulter was also beaten by a title favourite, going down 6-3 6-4 to 11th seed Aryna Sabalenka.
Fifth seed Kevin Anderson was the biggest name to fall so far but there were comfortable victories for Caroline Wozniacki and Maria Sharapova, who will meet in round three, as well as Rafael Nadal.
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It's all Greek
Anyone who remembers the 2006 Australian Open will remember the Greek fans who were such a part of Cypriot Marcos Baghdatis' run to the final. Melbourne has the biggest Greek population of any city outside of Athens, and now they have not one but two leading players to cheer.
Stefanos Tsitsipas and Maria Sakkari claimed battling victories one after another on a raucous Court Two, with Sakkari telling ausopen.com: "I love it. It fires you up. It's unbelievable because we don't have a tournament back home, so playing here is exactly how we would feel if we were playing in Greece."
Not so cute and furry
Meeting Australian animals is a staple when tennis players head Down Under but, if Sloane Stephens and Kim Clijsters were expecting koalas and kangaroos, they were in for a nasty shock.
Fallen seeds
Women: Kiki Bertens (9), Anett Kontaveit (20), Lesia Tsurenko (24), Donna Vekic (29)
Men: Kevin Anderson (5), Gael Monfils (30)
Who's up next?
Rarely can Rod Laver Arena have hosted such an exciting night session in only the second round, with Serena Williams taking on Eugenie Bouchard before a rematch of the 2008 final between Novak Djokovic and Jo-Wilfried Tsonga.
Britain's sole remaining survivor in singles, Johanna Konta, has her work cut out against two-time grand slam champion Garbine Muguruza in a match that will also be played at night.
Top seed Simona Halep meets fast-rising young American Sofia Kenin while Naomi Osaka, Venus Williams, Alexander Zverev and Stan Wawrinka are also in action.
