Murray, who had a bye in the first round, will next face either Grigor Dimitrov of Bulgaria or Simone Bolelli of Italy.

"I started well and was serving well throughout the match," Murray said. "I got jet lag and didn't sleep well for a few days." The match started after a ceremony presided over by Thai Prime Minister Yingluck Shinawatra.

Earlier, Donald Young eliminated defending champion Guillermo Garcia-Lopez of Spain 6-1, 6-7 (0), 7-5.

"It feels great to get a win like that," said Young, who missed an early chance to wrap up the match when serving at 5-3. "He won the tournament last year. It's a great scenario for me, it's great to move on into the quarterfinal.

"Holding my nerve was the key. I tried not to get down when I had the chance to serve for the match. I was up quite early in the first set. I had chances to break him in the second, but I didn't make it. I just tried to stay focused with the task in hand." Garcia-Lopez called for a trainer to attend a broken toenail.

"It is not the cause of my loss," the fourth-seeded Spaniard said. "I'm a professional tennis player. I just cannot play 100 percent all the time." Young next plays Go Soeda of Japan, who beat Tobias Kamke of Germany 6-2, 7-6 (7).

In Tokyo, An ankle injury forced Maria Sharapova to retire from her quarterfinal at the Pan Pacific Open in Tokyo on Thursday, allowing Wimbledon champion Petra Kvitova to progress to the last four.

Sharapova, trailing 3-4, twisted her left ankle in the eighth game against the Czech fifth seed, which beat her in the Wimbledon final in July.

"I landed awkwardly on my left ankle. I felt a sharp pain and the next thing I knew I was on the floor," the Russian said.

"It swelled up immediately and I knew there was no way I could continue." Kvitova faces Vera Zvonareva in the semi-finals after the Russian beat compatriot Maria Kirilenko 6-3, 6-3 in their quarterfinal.

Third seed Victoria Azarenka beat Marion Bartoli 7-5, 6-0 to set up a semifinal clash against Poland's Agnieszka Radwanska who beat Estonia's Kaia Kanepi 6-2, 7-6.

In Kuala Lumpur, Serbia's Viktor Troicki cruised into the quarterfinals of the Malaysian Open after beating Denis Istomin of Uzbekistan 6-1, 6-4 on Thursday.

The second-seeded Troicki, who had a bye in the first round, saved all three break points he faced to knock out Istomin in 79 minutes at Kuala Lumpur's Putra Stadium.

Fifth-seeded Nikolay Davydenko of Russia also advanced after battling hard to defeat Poland's Lukasz Kubot 6-3, 7-6(2) in one hour and 26 minutes.

Japan's Kei Nishikori also endured for more than two hours before sealing a 6-3, 4-6, 7-5 victory over Philipp Petzschner of Germany.