In the quarterfinal matches played today the 367-ranked Jakupovic of Slovakia, who enjoyed a career best ranking of 234 last year, ousted sixth seed Riko Sawayanagi of Japan who retired when trailing 3-6 0-1 due to a cramp in her back.
Jakupovic will take on 19-year-old Belgian left-hander Marie Beniot, ranked 443 in the semis.
Beniot, who won a USD 10,000 event in Egypt late last month, outplayed Briton Harriet Dart 6-2 6-0 in less than a hour to take a step closer to her first USD 25,000 event final.
Naydenova, who also has a USD 10,000 title to her credit, will take on another Chinese Xinyun Han in the semifinals.
The eighth-seeded Han scored a 7-5 6-1 quarter final win over Valentyna Ivakhnenko of Russia in 1 hour and 57 minutes.
