Defending champion Novak Djokovic has progressed to the third round after defeating Japanese wildcard Tatsuma Ito in Melbourne.
The Serb, who won 6-1, 6-4, 6-2 in one hour and 35 minutes, will now face Yoshihito Nishioka, who had crushed British number one Dan Evans in straight sets.
Sixth seed Stefanos Tsitsipas also reached the third round after opponent Philipp Kohlschreiber withdrew injured.
He will face Canadian Milos Raonic or Cristian Garin of Chile in the third round.


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