MELBOURNE: Bulg­arian Grigor Dimitrov held his nerve to knock home favourite Nick Kyrgios out of the Australian Open in a fourth-round thriller at the Rod Laver Arena on Sunday.

Third seed Dimitrov absorbed 76 winners and struck 64 of his own to prevail 7-6 (7-3), 7-6 (7-4), 4-6, 7-6 (7-4) and set up a quarter-final with unseeded Briton Kyle Edmund who beat Italian Andreas Seppi 6-7(4) 7-5 6-2 6-3.

Top seed Rafa Nadal was rattled by a feisty challenge from Diego Schwartzman but fought back strongly to move past the diminutive Argentine 6-3, 6-7 (4-7), 6-3, 6-3.

The 16-time Grand Slam champion, who was broken three times as he lost the third set, responded with grit to claim the win on the third match point with a rocketed backhand return.

Victory ensured that Nadal will retain his world number one ranking as he set up a meeting with sixth seed and former US Open champion Marin Cilic for a place in the semi-finals.

Cilic earlier ground down Spaniard Pablo Carreno Busta 6-7 (2-7), 6-3, 7-6 (7-0), 7-6 (7-3) at the Margaret Court Arena.

Second seed Caroline Wozniacki needed a shade over an hour to thrash Slovakia’s Magdalena Rybarikova 6-3, 6-0 and advance to the quarter-finals. The Dane next meets Carla Suarez Navarro who beat Estonian Anett Kontaveit 4-6, 6-4, 8-6.

Belgium’s Elise Mertens progressed to her maiden Grand Slam quarter-finals in her first appearance in the Australian Open main draw, beating Croatian Petra Martic 7-6 (7-5), 7-5.

Her opponent in the next round, Ukraine’s Elina Svitolina, firmed as a strong contender for the title with a flawless 6-3, 6-0 victory over Czech qualifier Denisa Allertova in the early hours of Monday morning.

Sunday’s results (prefix number denotes seeding):

Men’s singles:

Fourth round: 6-Marin Cilic (Croatia) bt 10-Pablo Carreno-Busta (Spain) 6-7 (2-7), 6-3, 7-6 (7-0), 7-6 (7-3); 3-Grigor Dimitrov (Bulgaria) bt 17-Nick Kyrgios (Australia) 7-6 (7-3), 7-6 (7-4), 4-6, 7-6 (7-4); 1-Rafael Nadal (Spain) bt 24-Diego Schwartzman (Argentina) 6-3, 6-7 (4-7), 6-3, 6-3; Kyle Edmund (Great Britain) bt Andreas Seppi (Italy) 6-7 (4-7), 7-5, 6-2, 6-3.

Women’s singles:

Fourth round: Carla Suarez Navarro (Spain) bt 32-Anett Kontaveit (Estonia) 4-6, 6-4, 8-6; 2-Caroline Wozniacki (Denmark) bt 19-Magdalena Rybarikova (Slovakia) 6-3, 6-0; Elise Mertens (Belgium) bt Petra Martic (Croatia) 7-6 (7-5), 7-5; 4-Elina Svitolina (Ukraine) bt Denisa Allertova (Czech Republic) 6-3, 6-0.

Published in Dawn, January 22nd, 2018