Cilic sends Roddick crashing out after five sets in Melbourne

CROATIA'S Marin Cilic continued his giant-killing run at the Australian Open to send former world number one Andy Roddick crashing out in five sets in Melbourne Park.

GIANT KILLER: 6'6'' Croat Marin Cilic backs up defeat of US Open champion Juan Martin Del Potro by sending Andy Roddick crashing out of the Australian Open (Getty Images)

The 21-year old had upset US Open champion Juan Martin Del Potro in five sets in round four to book his second consecutive grand slam quarter final appearance.

And despite throwing away a two set lead against seventh seed Andy Roddick, the 6'6'' Croat had a second wind and swept through the decider to prevail  7-6, 6-3, 3-6, 2-6, 6-3 and reach his first career grand slam semi final.

Both players had spent their fair share of time on court in Melbourne with Roddick coming through in five sets against Fernando Gonzalez in round four and Cilic having gone the distance twice himself against Del Potro and 17-year old Australian Bernard Tomic.

But while the Croat had seemed the fresher of the two as he outplayed Roddick during the first two sets, Cilic's energy levels dropped midway through the third set and the American started to dominate proceedings.

With his history of five-setters on Rod Laver Arena - Roddick came through 21-19 in the longest fifth set in history against Morroco's Younes El Aynaoui in 2003 - and captured momentum, the American started the final set as favourite.

But Cilic had showed signs of resurgence at the end of the fourth set and cranked up his level once again to edge the decider.

There were few shocked faces in the crowd as the first set was dominated by serve but while Cilic had looked the more likely to break, it was Roddick who drew first blood, breaking the Croat at the death to take a 6-5 lead.

But the 14th seed struck immediately back and sealed the opening set tie-break with a graceful forehand winner down the line.

The American bounced back with an early break in the second set but Cilic was seeing the ball too well and broke immediately back before completing a sumptuous set to take a 2-0 advantage.

Roddick looked fatigued and resigned to his fate as his 21-year old opponent hit a barrage of winners past the American and showed delightful touch at the net.

But the world number seven is known for his battling qualities and after claiming another early break in the third set, Roddick served out the set to gain a foothold in the match.

While the American was evidently tired, the stone-faced Cilic had also began to show his first signs of fatigue and a disbelieving Roddick steamrollered his way through the fourth set, reverting to a flat forehand which had served him so well at the start of his career.

An early break beckoned for Roddick for the fourth consecutive set as the American raced to 0-40 on his opponent's first service game of the decider.

But this time the Croat fought back, finding four first serves to reel off the next five points.

From his lifeless performance in the fourth set, Cilic was clearly saving something for the decider and so it proved as the Croat stepped up his level once again.

A break of serve at 3-1 proved decisive as Cilic confidently served out the set to set up a semi final clash with either defending champion Rafael Nadal or Andy Murray.