Japanese No. 1 and local star Kei Nishikori stunned Tomas Berdych to reach the semifinal in Tokyo on Friday.
Nishikori, seeded eight, had to strain to the limit to gain a 7-5, 6-4 victory at the Japan Open.
In the semis, the 22 year old will face Marcos Baghdatis of Cyprus, who beat Russian qualifier Dmitry Tursunov 6-2, 6-4.
It will be the fourth clash between the two, with world No. 46 Baghdatis winning all three on hard courts.
The second semifinal pair consists of reigning champion Andy Murray and sixth seed Milos Raonic of Canada.