The Spaniard, chasing a first Australian Open title since 2009, was forced to take a medical timeout midway through the fourth set after falling a break behind.

Cilic, who had matched the 16-time Grand Slam champion all the way, sensed his opportunity to force a decider and despite the obvious discomfort, Nadal began the fifth set only to be broken in his opening service game before bringing an end to the match, trailing 2-0 in the deciding set.

The Croatian world No 6 won 3-6 6-3 6-7(5) 6-2 6-0 in three hours and 47 minutes on Rod Laver Arena to reach only his second semi-final at Melbourne Park.