Melbourne - British fourth seed Andy Murray advanced to the quarter-finals of the Australian Open on Monday after his opponent Mikhail Kukushkin of Kazakhstan retired early in the third set with a hip injury.
The Scot was in total command when Kukushkin called it quits, leading 6-1, 6-1, 1-0 in hot conditions on Rod Laver Arena.
Murray, a two-time Melbourne finalist, now faces either French sixth seed Jo-Wilfried Tsonga or Japan's 24th seed Kei Nishikori in the last eight.
Kukushkin was treated for a left hip flexor injury during the match and looked well off the pace as he conceded eight service breaks in his 49 minutes on court.
Murray saved on some energy in the stifling heat ahead of his quarter-final on Wednesday.
"I played him a few weeks ago in Brisbane. It was a first round match and three tough sets and I was expecting another tough one today, it was so hot on the court," Murray said.
"So it's obviously good for me that I get to conserve a bit of energy, but tough for him. It's the first time for him in the fourth round of a slam, he was obviously struggling."