The top-seeded German Tatjana Maria advanced to the semi-finals of the Barranquilla Open after defeating the No 6 seed, Dutchwoman Suzan Lamens, 7-5, 7-5 on Friday night. Maria, ranked No 71, will now face Croat Antonia Ruzic in the next round. In earlier rounds, Maria beat Colombian wildcard Maria Herazo Gonzalez (6-0, 6-1) and American Elizabeth Mandlik (6-4, 4-6, 6-3). Lamens, ranked No 125, won against Israeli qualifier Lina Glushko (7-5, 6-1) and Francesca Jones (6-4, 1-6, 6-4) to reach this stage of the tournament.