Newport - Two-time champion John Isner, Aussie star Lleyton Hewitt and defending champ Nicolas Mahut all advanced to the second round at the Hall of Fame Tennis Championships on Tuesday.
American top seed Isner hammered 19 aces in a win over qualifier Wayne Odesnik 6-3, 7-6 (8/6) in the ATP Tour grass-court tournament.
Isner won consecutive titles at this event in 2011 and 2012, and is the number one seed in Newport for the third time in four years. Hewitt beat him in last year's semi-finals, snapping Isner's 13-match tournament win streak.
Isner advances to face another qualifier in fellow American Austin Krajicek, who defeated Tim Smyczek 7-6 (9/7), 6-1, on day two.
Meanwhile, former world number one Hewitt rallied to oust American Ryan Harrison 1-6, 7-5, 6-4, and the fourth-seeded Frenchman Mahut fired 11 aces in beating Argentine Facundo Arguello 7-6 (7/1), 6-4.
Mahut beat Hewitt in last year's Newport final, as the Australian lost for the second straight year in the championship match. Mahut was also the 2007 Newport runner-up to Fabrice Santoro.
In other matches on Tuesday, seventh-seeded Jack Sock eased past fellow American Alex Kuznetsov, 6-4, 6-3, eighth-seeded Frenchman Adrian Mannarino cruised past Taiwan's Jimmy Wang 6-2, 6-4, and Australian qualifier Luke Saville eliminated Canada's Peter Polansky 6-4, 6-2.
Ukrainian Sergiy Stakhovsky and Croatian qualifier Ante Pavic also won their first-round matches.
Results from the second day of the Hall of Fame Championships on Tuesday (x denotes seeded player):
John Isner (USA x1) bt Wayne Odesnik (USA) 6-3, 7-6 (8/6)
Austin Krajicek (USA) bt Tim Smyczek (USA) 7-6 (9/7), 6-1
Ante Pavic (CRO) bt Marius Copil (ROM) 7-6 (7/0), 6-4
Luke Saville (AUS) bt Peter Polansky (CAN) 6-4, 6-2
Nicolas Mahut (FRA x4) bt Facundo Arguello (ARG) 7-6 (7/1), 6-4
Adrian Mannarino (FRA x8) bt Jimmy Wang (TPE) 6-2, 6-4
Sergiy Stakhovsky (UKR) bt Farrukh Dustov (UZB) 6-3, 6-2
Lleyton Hewitt (AUS x3) bt Ryan Harrison (USA) 1-6, 7-5, 6-4
Jack Sock (USA x7) bt Alex Kuznetsov (USA) 6-4, 6-3