Nadal defies Nishikori as Muguruza bows out

It might have been straight sets, but Rafa Nadal's fourth-round win over Kei Nishikori at the Australian Open was anything but straightforward. Nishikori claimed the Nadal serve four times and was just one game shy of equaling the total the world number one had dropped so far in the tournament in a 6-7, 5-7, 6-7 loss.

"He played a fantastic match," said the 2009 champion, who lost his composure at a sticky stage of the match when the chair umpire called him up for a time violation at 4-4 and deuce in the third set. The world number one also had to contend with a sizeable welt on his left hand. But as so often with Nadal it was his blistering ground strokes that blazed a path to victory against the guileful game of Nishikori.

Nadal goes on to face Grigor Dimitrov in the quarterfinals after the Bulgarian 22nd seed brought the run of Spain's Roberto Bautista-Agut to a halt.

On Sunday, David Ferrer also booked his place in the last eight, again recovering from the loss of the first set to eventually see off Florian Mayer comfortably in a 6-7, 7-5, 6-2, 6-1 victory. The third seed will play Tomas Berdych in the quarterfinals, the Czech winning the battle of the towering servers against Kevin Anderson.

In the women's draw Spain's final representative, Garbiñe Muguruza, fell to world number five Agnieszka Radwanska despite a promising start. Still at 20, with a title and a deep Grand Slam run so far in 2014, the world number 38 is a star of the future.