DOHA, Qatar, Jan. 1 (UPI) -- Top-seeded Russian Nikolay Davydenko and third-seeded Brit Andy Murray won but second-seeded Tommy Robredo lost Tuesday at the Qatar Open. Davydenko, ranked fourth in the world, beat German Benedikt Dorsch 6-3, 6-0 and Murray beat Belgian Olivier Rochus 6-0, 6-2. Murray was last year's Doha runner-up to Croat Ivan Ljubicic. Davydenko next plays Frenchman Fabrice Santoro and Murray will meet German Rainer Schuettler. Robredo was upset by Argentine Agustin Calleri 6-4, 6-4. In another upset, Belgian Christophe Rochus defeated 6-foot-10 Croat Ivo Karlovic, the fifth seed, 7-6 (7-2), 6-2.