Britain’s Andy Murray needed only to appear on court at Rod Laver Arena to make it into his fifth successive grand slam quarter-final on Monday.
Murray, the fourth seed, took the first two sets from Mikhail Kukushkin of Kazakhstan 6-1 6-1 before his opponent withdrew from the match with a hip injury after losing the first game of the third set.
Kukushkin was clearly troubled by the problem throughout their fourth round match.
He offered only token resistance to Murray after previously playing one of the most entertaining matches of the championship to beat Frenchman Gael Monfils in five sets.
For Murray the win put him one match closer to the grand slam title he has come so close to on three occasions.
The runner-up at the past two Australian Opens, Murray was also a beaten finalist at the 2008 US Open.
He was also a semi-finalist in the final three grand slams of 2011.