Tormented by frustration and a tricky opponent, Roger Federer's [Images] customary cool slipped for a second on Wednesday as the Swiss hurled his racket during a hard-fought first round victory at the Thailand Open.

The Wimbledon [Images] and U.S. Open champion was made to battle all the way before beating Brazilian Marcos Daniel 7-6, 6-4 to open his Thai defence and the strain caused the uncharacteristic outburst.

"I was told he likes to get the rhythm and he's pretty slow from the baseline, and I get a guy serve and volleying at me," the world number one said.

"It's not so easy to adjust, plus on top of that I feel a little rusty coming from clay, but in the end I played some good shots when I needed them.

"There was some frustration here and there. It shouldn't have happened, but it did."

Federer's frustration was understandable as 133rd-ranked Daniel refused to be intimidated by the stature of his opponent and rallied well from the baseline.

DIFFICULTY ADJUSTING

At one stage Federer came within two points of allowing Daniel to serve for the opening set, and he had to wait until his eighth break point before a backhand volley error from Daniel at 5-5 gave him the first break of the match.

Even then he dropped his own serve, and just one mini-break -- on the first point of the tiebreak -- decided the set in Federer's favour.

Several break points also went begging in the second set, before Federer finally claimed victory on his third match point.

Lleyton Hewitt [Images] also struggled to overcome a dogged opponent before reaching the second round.

Second seed Hewitt, playing his first match since losing to Federer in the semi-finals of the U.S. Open, survived an enterprising challenge from Czech Lukas Dlouhy to win 6-3, 3-6, 7-5.

The Australian appeared set for a runaway victory as he swept to a 4-1 lead in the opening set, but once Dlouhy settled he offered a real challenge.

"I probably played the tighter points a bit better than he did out there," said Hewitt, who admitted he had difficulty adjusting to playing indoors after the U.S. Open.

"Everything felt very different out there today, and it was just a question of trying to get through that match.

"Throughout the first and seconds sets I actually felt he was playing my service games a lot better than his own. He threw in a lot of double-faults and some cheap second serves for me for me, but he hit the ball really well from the back of the court."

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