Argentina's David Nalbandian recovered from a mid-match slump to see-off a brave challenge from little-known Thai player Danai Udomchoke in the first round of the Australian Open on Monday.

World number eight Ivan Ljubicic also survived a tricky Australian Open first round encounter to beat local wildcard Chris Guccione 7-6, 6-4, 7-6.

Fourth seed Nalbandian had appeared set for an easy passage into the second round after dominating the first two sets, but lost power and rhythm in the third as Danai fought back with ripping ground strokes.

Danai took the third and fourth sets but wilted in the fifth, allowing Nalbandian to close out the match 6-2, 6-2, 1-6, 6-7, 6-1.

"In the middle of the third set I lose power, lose everything, don't feel good," Nalbandian said, adding he was still recovering from a recent illness.

"I expect to be better physically but I'm not 100 percent yet," he told reporters.

Danai broke Nalbandian's serve for the first time in the fourth game of the third set before repeating the feat two games later to race to a 5-1 lead.

The qualifier went toe-to-toe with Nalbandian in the fourth to force a tiebreak -- which he won 7-4 -- setting up a deciding fifth set.

But Nalbandian regrouped to grab a 3-0 lead in the fifth and the Thai, playing in Melbourne main draw for the first time, needed treatment for a back injury.

Danai, 24, said his back was sore after a tough qualifying tournament and that he felt burning pain after being treated with heat cream by a tournament physiotherapist.

Nalbandian, the Masters Cup champion, held on to win on his second match point after three-and-a-half hours.

"It's not the best way to start but it's good always to win, the score doesn't matter," Nalbandian said.

SHADOW OF SRICHAPHAN

Nalbandian has reached the quarter-finals in Melbourne for the past three years and is rated as one of the few men in the draw with a realistic chance of challenging world number one Roger Federer [Images].

"If I play good I can beat anyone," said Nalbandian, who came from two sets down to beat Federer in the season-ending Masters Cup final in Shanghai.

Danai, ranked 121st in the world, admitted to suffering from nerves and over-excitement in the first two sets after making the main draw on his sixth attempt.

"I tried not to think about the nerves and to focus on the ball," Danai said. "After the third set I thought I could beat this guy."

Danai has long played in the shadow of his better-known compatriot Paradorn Srichaphan [Images] and was competing in only his third grand slam event after making his way through the qualifiers at the 2004 U.S. Open and Wimbledon last year.

"Now more people know me in Thailand, but not like Paradorn. He's like a king," Danai said.

LJUBICIC THROUGH

Ljubicic and Guccione were evenly matched throughout the contest with the Croat seizing the advantage when he broke Guccione once each in the second and third sets.

Guccione used his powerful serve to attack the net, winning more than half his points from the front of the court, but he made 17 unforced errors to Ljubicic's nine.

Ljubicic has advanced past the second round of the Australian Open just once, in 2002 when he made the third round.

He will meet Philipp Kohlschreiber in the second round after the German beat Czech Republic's Lukas Dlouhy 7-5 6-2 6-4.

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