Australian Open: Cilic storms into semifinal as Nadal retires

Marin Cilic was leading 2-0 in the fifth and final set when Rafael Nadal walked off injured. This is the second time the Spaniard has retired from a Grand Slam, the first in 2010 against Andy Murray in the Australian Open.

Marin Cilic exults after his match against Rafael Nadal.   -  AP

Rafael Nadal's Australian Open hopes were dashed in cruel fashion as he retired through injury in the fifth set of his quarterfinal against Marin Cilic.

Former US Open champion Cilic produced a hugely impressive display on Rod Laver Arena, his stinging, flat forehands a particularly potent weapon throughout a contest that was brought to a premature end after three hours and 47 minutes.

However, the Croatian was significantly aided by a clear deterioration in the fitness of Nadal, whose movement was compromised after he called for a medical timeout in the fourth set.

Although Nadal initially continued after receiving prolonged treatment on his upper right leg, he was ultimately unable to compete and retired when trailing 3-6, 6-3, 6-7(5), 6-2, 2-0.

Cilic will now face surprise package Kyle Edmund in the last four, with hopes of a rematch of last year's final between Nadal and Roger Federer having been sensationally ended.

Rafael Nadal receives medical attention during his quarterfinal against Marin Cilic.   -  AFP

The seriousness of Nadal's injury remains to be seen, but the top seed cut a forlorn figure as he exited the court to sympathetic applause, a day on from an ailing Novak Djokovic suffering defeat to Hyeon Chung.

Nadal failed to initially capitalise when a succession of Cilic errors provided him with five chances to break in the sixth game, but the world number one soon seized control before sealing the opening set with a forehand winner.

Cilic then fell behind early in set two, double faulting on break point after receiving a time violation, but a swift turnaround followed with the Croatian seemingly fired up by the umpire's intervention.

The aggrieved sixth seed duly reeled off four games in a row to level the match, enjoying particular success against Nadal's second serve as he adopted a more aggressive approach.

Read: Cilic sympathises with injured Nadal

Amid rising tension, both men were showing emotion on an increasingly regular basis and a reflex volley from Nadal was followed by a trademark fist pump as he stopped the rot in the first game of the third set with a crucial hold.

After saving three break points and spurning a solitary opportunity of his own when leading 5-4, there was an even bigger reaction when the Spaniard eventually regained the advantage at the end of an absorbing tie-break.

Nadal let out a huge roar to celebrate putting away a smash on set point, but Cilic came storming back once again to break for a 3-1 lead in the fourth.

Out of the blue, Nadal then called for a medical timeout at the next changeover and received prolonged treatment.

His movement was significantly limited thereafter, even though he came from 0-40 down to hold in the next game, and Cilic suddenly looked a strong favourite as he broke again to force a decider.

That final set ultimately lasted just two games, Nadal bringing an end to proceedings after he had bravely saved five break points before finally falling 2-0 down.

Cilic now has a golden opportunity to reach his third Grand Slam final, while Nadal will await news on another painful injury setback.