Tien Minh, who defeated Wong Wing Ki of Hong Kong 21-17, 21-17, had denied Wei Feng his first title at the 2009 Vietnam Open.
Indonesian back-up player Wisnu Yuli Prasetyo ousted China Masters runner-up Hu Yun of Hong Kong 19-21, 21-12, 21-17 while Chou Tien Chen of Taiwan beat compatriot Hsueh Hsuan Yi 21-11, 21-15 in the quarter-finals.
The regular training with World No 1 Lee Chong Wei seems to be bearing fruits for Wei Feng. Even Arif has shown a marked improvement.
Prior to the London Olympics, Wei Feng and the other senior shuttlers served as Chong Wei's sparring partners. Chong Wei has also been helping the younger players in training for the last two months.
Malaysia also saw further success in the men's doubles with independent pair Zakry Latif-Fairzizuan Tazari and national back-up combination Owe Yao Han-Chooi Kah Ming advancing to the semi-finals.
Zakry-Fairuz defeated Chan Tsz Kit-Lo Lok Kei of Hong Kong 21-16, 21-16, and will meet Taiwan's Chen Hung Ling-Lu Chia Bin while Yao Han-Kah Ming, who beat Taiwan's Cheng Chun Jen-Lin Yen Jui 21-18, 13-21, 21-11, will take on top seeds Angga Pratama-Ryan Agung Saputra of Indonesia.
Women's doubles Vivian Hoo-Woon Khe Wei made the last four after beating Huang Mei Ching-Wen Kuo Yu of Taiwan 21-12, 21-7 and will play Bernadeth Pia Zabedah-Rizki Amelia Pradipta today.
Khe Wei also reached the mixed doubles semi-finals with Ong Jian Guo with a 21-10, 21-19 win over second seeds Danny Bawa Chrisnanta-Vanessa Neo of Singapore. They will next play Hong Kong's Lee Chun Hei-Chau Hoi Wah.