Beijing Olympics and three times world champion Lin Dan booked a much anticipated semifinal clash with world number one Lee Chongwei at the China Masters badminton super series?in Changzhou?on Friday.

With two rounds to go, hosts China already booked three titles in the women's singles, women's doubles and mixed doubles.

Lin edged South Korean top player Park Sung Hwan 21-15, 13-21, 23-21 in a hard-fought quarterfinal before Beijing Games runner-up Lee eased past China's Du Pengyu 21-19, 21-15 to set up a rematch with Lin.

Lin squandered five match points after leading 20-15 before he clinched the win in 69 minutes, the second longest match in the men's singles by far at this tournament.

"I was slow to find my form because I was not quite concentrated. After the world championships, I have been more focused on preparing for the national games," said the 26-year-old.

"To be honest, I was given a cold sweat by Park, who was perseverant and played well today," he added.

Lee said he was prepared to face Lin.

"I am well prepared now. Lin is a long time rival of mine, so I'd better keep a good state of mind," said Lee, 27.

The Danish ship completely sank at this six-day tournament when third seed Peter Gade, the last Dane left at the event, lost to Thailand's Boosak Ponsana 21-16, 19-21, 21-18.

World number three Gade protested as the umpire ruled a Ponsanastroke inside when he led 11-10 but was met with a warning.

The 32-year-old admitted that he was affected by the rule.

"The umpire made mistakes and I said 'what happened'. But she gave me warnings. (I was) angry," he said.

In the last men's singles match, world number two Chen Jin beat fellow Chinese Chen Long 21-16, 8-21, 21-16.

China effectively secured the three titles after Chinese players swept the respective quarterfinals.

In the women's singles, qualifier Wang Xin stunned French seventh seed Pi Hongyan 21-11, 21-10 following her surprising win over fifth seeded Dane Tine Rasmussen in the second round.

World championships bronze medalist Wang Lin worked her way past South Korean Kim Moon Hi 21-19, 21-18 to face Wang in the last four.

Wang Shixian, 19, overcame All England Open titlist Wang Yihan 21-18, 21-18 to face reigning world champion Lu Lan who brushed aside world number one Zhou Mi from Hong Kong, China, 21-10, 21-17.

All-England Open mixed doubles winners He Bin/Yu Yang eliminated the only non-Chinese pairs Ko Sung Hyun/Ha Jung Eun from Sout Korea 21-15, 21-17 to set up a semifinal clash with Xie Zhongbo/Ya Yawen who pushed aside Zheng Bo/Tian Qing 21-13, 21-18.

Chen Zhiben/Zhang Jinkang and Tao Jiaming/Wang Xiaoli each won their all-Chinese quarterfinals to advance.

Top seeded women's doubles duo Cheng Shu/Zhao Yunlei continued their run for a successful defense of the title as they beat ZhangDan/Zhang Zhibo from Macao, China, 21-18, 21-16 and Pan Pan/Tian Qing clinched a 21-16, 21-19 win over former Olympic champions Yang Wei/Zhang Jiewen who retired from the national team last year.

Beijing Olympics champions Du Jing/Yu Yang pulled off the victory over teammates Ma Jin/Wang Xiaoli 19-21, 21-12, 21-12 to take on Gao Ling/Wei Yili.

World champions Cai Yun/Fu Haifeng next meet South Korean Cho Gun Woo/Yoo Yeon Seong in the men's doubles semifinals where Choong Tan Fook/Lee Wan Wah from Malaysia play China's Guo Zhengdong/Xu Chen.