Eighth-seeded Go Soeda of Japan overcame a nearly three-hour rain delay to beat Belgium's Xavier Malisse 4-6, 7-5, 6-4 in the first round of the Atlanta Open on Tuesday.
Soeda advanced to a second-round clash with Russia's Igor Kunitsyn.
Matthew Ebden of Australia held off qualifier Sergei Bubka of Ukraine 5-7, 6-1, 6-1, and will next meet either Ryan Harrison or Jame Blake.
Michael Russell came from a set down to beat Alex Kuznetsov 2-6, 6-4, 7-6 (4), setting up a second-round match with fifth-seeded South African Kevin Anderson.
John Isner, the No. 1 seed, and two-time defending champion Mardy Fish, the second seed, will play their first-round matches on Thursday.