Rafael Nadal was gifted an easy passage into the quarter-finals of the Australian Open when his fourth-round opponent, Paul-Henri Mathieu, retired hurt.
The world number two was leading 6-4 3-0 when the French 23rd seed called an early halt to proceedings.
Spaniard Nadal forced the first break of serve in game three of the opening set, and just two games later Mathieu showed the first signs of injury when he called for the trainer to treat a troublesome lower leg.
Mathieu was able to continue but Nadal went on to wrap up the set in 40 minutes and had also won the first three games of the second when the Frenchman decided to retire.
Nadal will now face Finland's Jarkko Nieminen in the last eight.
'It's a little disappointing because I was playing a great match,' Nadal told reporters.
'I felt my best today, but I can't be (that) disappointed because I am in the quarter-finals.'
'Nieminen is very tough, a fighter," Nadal said. 'It's going to be an interesting match. I have to continue to play in this way.'
