Britons Dan Evans and Cameron Norrie reached the second round of the Nature Valley International at Eastbourne with straight-set victories.
Evans progressed with a 7-6 (7-2) 6-2 win over Moldovan Radu Albot and will face France's Pierre-Hugues Herbert or American Denis Kudla next.
Norrie, 23, beat Frenchman Jeremy Chardy 6-3 7-6 (7-4) in a match delayed by rain on Monday.
He will play British number one Kyle Edmund, the third seed, in round two.
World number 31 Edmund has a first-round bye.
Norrie, the British number two, saved a set point at 5-6 in the second set before sealing victory on his first match point.
Evans, 29, saved nine of the 10 break points he faced against Albot in the first set, which he took on a tie-break.
It was more straightforward in the second set as two breaks of serve ensured victory in one hour and 46 minutes.
Evans had lost to Albot in the final of the Delray Beach Open in February.
Potential opponent Kudla got into the draw as a lucky loser after Queen's singles and doubles champion Feliciano Lopez withdrew from the event because of fatigue.
Evans, now ranked 65 in the world, won back-to-back titles at Surbiton and Nottingham this month but lost in the first round of Queen's to Stan Wawrinka.
There were defeats for two other Britons in the men's event with 20-year-old Jay Clarke losing 6-7 (5-7) 6-1 6-3 to Argentine Juan Ignacio Londero, and James Ward, 32, beaten 2-6 6-3 6-1 by Italian Thomas Fabbiano.
French sixth seed Gilles Simon defeated American Tennys Sandgren 7-5 6-1 and plays Chile's Nicolas Jarry in the second round.