DELRAY BEACH, Fla. -- Second-seeded John Isner advanced to the third round of the Delray Beach Open on Wednesday night, beating Lukas Lacko of Slovakia 6-4, 6-3.
The American player set up a match against eighth-seeded Adrian Mannarino of France, a 6-2, 7-6 (3) winner over Denis Istomin of Uzbekistan in the outdoor hardcourt event at Delray Beach Stadium & Tennis Center.
England's Dan Evans followed his opening victory over third-seeded defending champion Frances Tiafoe with a 6-0, 6-2 win over Lloyd Harris of South Africa. Evans will face sixth-seeded Andreas Seppi of Italy, a 6-3, 4-6, 6-1 winner over Australia's Jordan Thompson.
Top-seeded Juan Martin del Potro of Argentina, playing his first event after missing four months because of a right knee injury, will face American Reilly Opelka in a second-round match Thursday night.