Tim Wilkison, fresh from a surprise win over Wimbledon champion Boris Becker, routed Glenn Michibata of Canada, 6-1, 6-2, Thursday to advance to the quarterfinals of the $279,000 WCT-Atlanta tennis tournament.
In a pair of upsets, fifth-seeded Paul Annacone lost to David Pate, 7-5, 6-4, and seventh-seeded Tim Mayotte was ousted by Brian Teacher, 6-3, 6-7, 6-3.
Kevin Curren defeated John Sadri, 7-6, 7-6, and Mikael Pernfors of Sweden defeated Andrei Chesnokov, the No. 1 player in the Soviet Union, 7-5, 7-6.
At Houston, top-seeded Mats Wilander of Sweden struggled in the second set before rallying to defeat Yugoslav teen-ager Bruno Oresar, 6-3, 2-6, 7-5, in a second-round match of the $200,000 River Oaks tournament.
Two other seeded players were upset. Fourth-seeded Thierry Tulasne of France lost to hometown favorite Harold Solomon, 7-6, 7-5, and eighth-seeded John Lloyd lost to SMU amateur Richie Reneberg, 6-2, 6-3.
At Marco Island, Fla., top-seeded Chris Evert Lloyd, playing her second match in 24 hours, defeated fifth-seeded Kathy Rinaldi, 6-1, 6-3, in the quarterfinals of the $150,000 Chrysler-Plymouth tournament.
In another quarterfinal match, second-seeded Claudia Kohde-Kilsch of West Germany came back from a 3-1 deficit to beat sixth-seeded Gabriela Sabatini, 6-3, 6-2.