Vietnam's badminton ace Nguyen Tien Minh won a final berth at the US Open Grand Prix after beating German rival Marc Zwiebler 2-1 in Los Angeles on Friday local time.
The 9th-ranked Vietnamese was expected to be beat the 17th-ranked German because he had won all their three previous encounters.
But the 6th-seeded German pulled off a surprise, winning the first set 22-20.
Minh stepped up his game to take the second set 21-13, but the third was a closely fought set with players level most of the time before Minh took it 21-18.
In the final match, Minh will face 15th-ranked Japanese Sho Sasaki, who defeated the 46th-ranked Taiwanese player Hsuan Yi Hsueh in straight sets in the other semifinal match.
Minh is expected to have a chance to beat the Japanese in the final to win the first championship this year because the Japanese rival is not too strong for Minh.
The finalists have met five times previously and Minh has won four of them, but Sasaki's lone victory came at the 2011 Australian Open in April.