Top seed Novak Djokovic [Images] breezed into the quarter-finals of the $576,000 Thailand Open after a 6-1, 6-3 victory over German qualifier Simon Stadler on Thursday.

Djokovic, the world number three, darted through the first set but the German adapted to his serves and tested him more in the second, although the Serb's victory was never in doubt.

"I was surprised the way I played in the first set," Djokovic told reporters. "The second set was a bit difficult as I couldn't get the first serve percentage high."

One of the sport's most colourful characters, Djokovic delighted the Bangkok crowd with one of his trademark impersonations, mimicking Thai favourite Paradorn Srichaphan [Images] by bowing repeatedly to the crowd with his palms pressed together.

"I taught myself to do that. I watched Paradorn and he was watching me play tonight," he said.

Djokovic will next play sixth seed Robin Soderling, who thrashed Russian Teimuraz Gabashvili 6-1, 6-3.

The Swede never gave the Russian a chance to get into the match, racing through each set in 23 minutes, firing 11 aces and double-faulting only once.

Unseeded Frenchman Nicolas Mahut progressed to the last eight for the second successive year after beating Finland's Jarkko Nieminen 6-4, 3-6, 6-3.

At one set each in a close match, Mahut took control at 3-3, playing an effective serve-and-volley game to send the fifth-seeded Finn packing.

"I'm happy to reach the quarter-finals for two years in a row. Indoor is my favourite surface," Mahut told reporters. "The serve and volley was my weapon today."

Mahut will play third-seeded Czech Tomas Berdych, who advanced after beating Italy's [Images] Simone Bolelli 7-5, 6-1.

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