Australian Hewitt recovered from two sets to one down to deny the 18-year-old Nadal a place in his first Grand Slam quarterfinal.

"In the fourth set, I had big chances," Nadal told reporters.

"I had three times 15-30, and at 4-4 I had 15-30.

"Today I didn't play bad in the important moments, but he played very, very good in the important moments, and he won because of that."

In front of a packed crowd at the Rod Laver Arena, Nadal dominated Hewitt for long periods as his sizzling forehand worked to perfection.

Hewitt snatched the fourth set in a tiebreak and with the Spaniard suffering from leg cramps the home favourite held on to clinch the decider 6-2.

Nadal, who ended 2004 in style by beating world number two Andy Roddick to help Spain defeat the United States in the Davis Cup final, was proud of his performance.

"I am happy because I played a good match and I had a lot of chances for a win," he said.

"I am happy because he is number three in the world and I played the same as him today. If I play at this level, I can do important things this year."