ATLANTA — Top-seeded John Isner started his bid for a fifth Atlanta Open title by beating Alex de Minaur of Australia 6-3, 6-2 on Wednesday night.
Isner is the defending champion at Atlantic Station, and he also won the event in 2013, 2014 and 2015.
The 6-foot-10 former University of Georgia star won the Miami Open in April for his 13th ATP Tour title and first Masters 1000 event victory.
Isner set up a quarterfinal match against seventh-seeded Mischa Zverev of Germany, a 6-4, 6-2 winner over Russia’s Mikhail Youzhny.
Eighth-seeded American Ryan Harrison, the losing finalist last year, advanced with a 2-6, 6-2, 6-3 victory over Lukas Lacko of Slovakia.
Third-seeded Hyeon Chung of South Korea beat American Taylor Fritz 6-4, 7-6 (5) to set up a quarterfinal against Harrison.