Bogota - Top-seeded Ivo Karlovic of Croatia overcame a slow start to defeat veteran wild card Radek Stepanek of the Czech Republic 3-6, 7-6 (7), 6-4 on Friday to reach the Claro Open semifinals.
The 23rd-ranked Karlovic will next play third-seeded Adrian Mannarino of France, who beat seventh-seeded Malek Jaziri of Tunisia 1-6, 6-1, 6-3.
The other semifinal in the ATP 250 clay-court tournament will be between Michael Berrer and Bernard Tomic.
German Berrer defeated Victor Estrella Burgos of the Dominican Republic 6-3, 3-6, 6-3 while Australia's Tomic cruised past Tatsuma Ito of Japan 6-1, 6-4.