Malaysian top seed Lee Chong Wei beat Dane Peter Gade 21-17 21-14 to make the final of the All England Championships for the second successive year.
Chong Wei faces unseeded Kenichi Tago in Sunday's final as the Japanese beat China's Bao Chunlai 18-21 22-20 21-18.
In the women's singles, 2008 champion Dane Tine Rasmussen edged out Indian seventh seed Saina Nehwal 21-19 21-17.
Rasmussen can avenge last year's final loss against China's Wang Yihan, who beat compatriot Wang Xin 21-17 26-24.
Gade had matched Chong Wei early on in the opening set but the Malaysian eventually stretched into a 17-11 lead which proved too much for the Dane.
In the second, Chong Wei took control at 15-13 in front as Gade had no reply for the world number one's cross-court smashing and neat net work.
Chong Wei, chasing his third Super Series win of the year at the National Indoor Arena in Birmingham, said: "I'm really pleased to make the final. It's very important for Malaysian badminton. We've not had anyone there for a while."
Chong Wei, 33, lost last year's final to world and Olympic champion Lin Dan but the Chinese second seed was knocked out in Friday's quarter-finals by Chunlai.
The men's doubles final, meanwhile, will be an all-Danish affair for the first time since 1967.
Matthias Boe and Carsten Mogensen beat China's Guo Zhendong and Xu Chen 21-16 21-16 to set up a meeting with Lars Paaske and Jonas Rasmussen, who defeated third seeds Markis Kido and Hendra Setiawan of Indonesia 14-21 21-13 23-21.