Andy Murray reached the semi-finals of the Sydney Tennis Classic when eighth seed David Goffin was forced to retire injured from their last-eight match.
Britain's former world number one claimed the first set 6-2, at which point Goffin was unable to continue.
It is the first time Murray, 34, has won three matches in a row at tour level since taking the European Open title in October 2019.
Murray will face 6ft 11in American Reilly Opelka in the last four.
Murray produced some impressive tennis after being pushed all the way in a three-hour match with Georgia's world number 23 Nikoloz Basilashvili, who he will face in the opening round of the Australian Open.
The three-time major winner raced into a 3-0 lead and saved break points at 3-1 with Goffin overhitting a second-serve return.
Goffin - whose 2021 season was ended early by a knee issue - called for a trainer for treatment on his knee before later deciding he could not continue.
Britain's third seed Dan Evans faces American Maxime Cressy in his quarter-final later on Thursday.
Elsewhere, British number four Liam Broady beat Jeffrey Wolf 3-6 6-4 6-4 to reach the Australian Open's final qualifying round, where he will face Russia's Roman Safiullin on Friday.
Harriet Dart, the only Briton remaining in women's qualifying, will play Australian wildcard Kimberly Birrell for a place in the main draw.