Top-seeded Pablo Andujar of Spain, Andreas Seppi of Italy and David Nalbandian of Argentina won Friday to reach the Serbia Open semifinals.
France's Benoit Paire also advanced to the last four after beating third-seeded Jarkko Nieminen of Finland 0-6, 6-, 7-5. Nieminen was playing his second match of the day, having beaten Croatian qualifier Antonio Veic 6-3, 4-6, 6-3 in a second-round match that was halted Thursday at 5-3 because of rain.
Andujar defeated Lukas Rosol of the Czech Republic 6-4, 6-3 and will face Paire on Saturday.
Second-seeded Seppi beat eighth-seeded Gilles Muller of Luxembourg 6-4, 6-3, never losing serve and breaking his opponent three times. Seppi will face Nalbandian, who defeated Joao Souza of Brazil 6-3, 6-2. Nalbandian converted three of his four break points and dropped serve just once.