Elsewhere , Spain 's fourth seed David Ferrer cruised past Japan 's No . 17 seed Kei Nishikori with a 6-1 6-2 6-4 win to set up a clash with fellow countryman Nicolas Almagro . Defending champion Novak ##ović survives five - set epic to defeat Stanislas Wawrinka . Serbian world No . 1 wins 7 - 6 7 - 5 6 - 4 6 - 4 12 - 10 to maintain Australian Open defense . David Adams , Nicolas Almagro and Tomas Beck all through to quarterfinals . Maria Sharapova , Agnieszka Radwanska and Li Na through to last 16 in women 's draw .
Defending champion Novak ##ović survives five - set epic to defeat Stanislas Wawrinka . Serbian world No . 1 wins 7 - 6 7 - 5 6 - 4 6 - 4 12 - 10 to maintain Australian Open defense . David Adams , Nicolas Almagro and Tomas Beck all through to quarterfinals . Maria Sharapova , Agnieszka Radwanska and Li Na through to last 16 in women 's draw .