British number three Kyle Edmund progressed to the second round of the Nastase Tiriac Trophy with victory over Lukas Rosol in Bucharest.
The South Africa-born 21-year-old beat his 30-year-old Czech opponent in straight sets 7-6 (7-4) 7-6 (7-5).
Meanwhile, the British number two Aljaz Bedene begins his Barcelona Open campaign later on Monday.
The Slovenia-born 26-year-old plays Russian qualifier Karen Khachanov, 19, in the first round.