Second-seeded Taylor Fritz of the United States beat Andrej Martin 6-2, 7-6 (4) on Wednesday to reach the quarterfinals of the Sardegna Open.
Fritz will next face Aljaz Bedene after the Slovenian overcame Egor Gerasimov of Belarus 6-4, 7-6 (5).
Fifth-seeded Jan-Lennard Struff of Germany eased past British qualifier Liam Broady 6-4, 6-2 to book a quarterfinal against Nikoloz Basilashvili.
The fourth-seeded Basilashvili had to save five match points before eventually securing a 4-6, 6-4, 7-5 victory over Slovakian qualifier Jozef Kovalik.
The ATP 250 tournament at the Cagliari Tennis Club was inserted into the calendar with a one-year license, following a similar event at Forte Village in October.