Nadal downs Cilic in Melbourne

Melbourne - Rafael Nadal played his best high-intensity match of the Australian Open to see off Marin Cilic and reach the quarter-finals on Monday.

The world number one, bidding for a fourth straight major title to complete a non-calendar year Grand Slam, was too strong for the 15th-seeded Croat, winning 6-2, 6-4, 6-3 in 2hr 31min on Rod Laver Arena.

Nadal will now play close friend and Spanish seventh seed David Ferrer in Wednesday's quarters. He leads Ferrer 11-3.

It will be Nadal's fifth successive Australian Open quarter-final and he stretched his Grand Slam winning streak to 25 matches, his longest, but four off the record run of 29 held by Rod Laver.

"Before tonight's match I was a little nervous because Cilic can play very aggressively and is very dangerous," Nadal said.

"I tried to play at a high intensity and I feel I played my best match so far at this year's Open."

Nadal said he felt no effects of the virus which he brought into the Open, and noticeably did not sweat anywhere near as much as he did in his third-round win over Australian teen Bernard Tomic.

"I didn't sweat as much tonight," he said. "Two days ago I was sweating like crazy and I felt tired, but today is the first day that I felt perfect physically."

Nadal broke Cilic's serve five times and hit 26 winners and 21 errors. Cilic only got two break point opportunities in the entire match and failed to convert.

Cilic was backing up after his marathon five-setter with American John Isner over four-and-a-half hours on Saturday.

He recorded his best Grand Slam performance by reaching last year's semi-finals, where he lost to Andy Murray, and will now lose ground in the next rankings after the Open.