French second seed Toma Junior Popov and unseeded Indonesian Chico Aura Dwi Wardoyo are set to meet in the final of the Badminton World Federation (BWF) Spain Masters at the Palacio de Deportes Carolina Marín in Huelva following semi-final victories.
In his tie, Popov thrashed unseeded South Korean Lee Dong-keun 21-7, 21-10, claiming an expected win.
What was not expected was Dwi Wardoyo's win over his compatriot and top seed Shesar Hiren Rhustavito, with the game finishing 21-16, 21-19.
The women's singles final will see Danish third seed Line Christophersen play Indonesia's Putri Kusuma Wardani.
Christophersen came through her semi-final, defeating unseeded Swiss player Jenjira Stadelmann 21-9, 21-19.
Wardani defeated France's Léonice Huet emphatically to make the final winning 21-8, 21-14.
Scottish seventh seeds Julie MacPherson and Ciara Torrance suffered a surprise loss to unseeded Indonesians Yulfira Barkah and Febby Valencia Dwijayanti Gani in the women's doubles semi-finals, with the score finishing 21-10, 21-14.
They are set to play Danish top seeds Amalie Magelund and Freja Ravn, who came from a game down to defeat Dutch pair Alyssa Tirtosentono and Imke van der Aar 17-21, 21-15, 21-14.
In the men's doubles, Indonesians Sabar Karyaman Gutama and Moh Reza Pahlevi Isfahani made it through to the final after a three-game win over Adam Hall of Scotland and Denmark's Frederik Søgaard 21-19, 13-21, 21-14.
Fifth seeds Pramudya Kusumawardana and Yeremia Erich Yoche Yacob Rambitan of Indonesia came from a game down to overturn French brothers Christo and Toma Junior Popov, making the final following a 18-21, 21-19, 21-14 victory.
Finally in the mixed doubles, top seeds Rinov Rivaldy and Pitha Haningtyas Mentari of Indonesia made it through to the final in straight games against Scottish fourth seeds Hall and MacPherson 21-16, 21-15.
Completing the day, Denmark's second seeds Niclas Nohr and Amalie Magelund defeated The Netherlands' Ruben Jille and Imke van der Aar 21-11, 18-21, 21-6 to join them in the final.