Amos Mansdorf of Israel upset top-seeded Jimmy Connors, 6-4, 6-3, Wednesday in the opening match of the $200,000 Gunze World tournament at Kobe, Japan.
Connors appeared to lose concentration after protesting a line call while ahead, 3-2, in the opening set.
Connors, 34, could not gain his rhythm in the second set. Mansdorf, 21, ranked 36th in the world, took the first four games and went on to beat Connors, the world's ninth-ranked player, in 87 minutes.
Unseeded Pavel Vojtisek of West Germany upset third-seeded Tim Mayotte, the top American hope, 5-7, 7-6, 6-2, in the completion of an opening-round match of the $615,000 Shearson Lehman Brothers Tournament of Champions in New York.
Vojtisek, ranked 127th in the world, rallied to win after Mayotte seemed in control with a 5-2 lead in the second set. The match was suspended by darkness Tuesday after the second set.
In another upset, Andreas Maurer of West Germany eliminated No. 13-seeded Christo van Rensburg of South Africa, 7-5, 6-4.
Many players were forced to play two matches Wednesday after two days of rain delays.
Top-seeded Boris Becker of West Germany needed only 21 minutes to win his first contest when Francisco Maciel withdrew with a foot injury, but Becker had to struggle for 3 hours 4 minutes to subdue Juan Avendano of Spain, 7-6, 5-7, 6-2.
Fifth-seeded Pat Cash of Australia wasn't so lucky. After winning the last five games to turn back Brett Dickinson, 6-7, 6-4, 7-5, Cash was eliminated by Canadian qualifier Martin Wostenholme, 6-2, 6-4.
Ninth-seeded Jimmy Arias downed Jay Lapidus, 6-4, 6-2, but then was ousted by Marty Davis, 7-6, 6-4. Eliot Teltscher was beaten by South African Barry Moir, 2-6, 6-3, 6-1.
The only seeded American players reaching the third round were No. 10 Aaron Krickstein, a 6-4, 6-3 winner over Alberto Tous of Spain, and No. 11 Jay Berger, who beat Sammy Giammalva, 6-4, 7-6.
In night matches, second-seeded Yannick Noah of France and No. 7 Guillermo Vilas of Argentina also won third-round berths, Noah crushing West Germany's Damir Keretic, 6-1, 6-2, and Vilas defeating Eric Fromm, 6-2, 6-1.
Third-seeded Helena Sukova outlasted fellow Czech Regina Marsikova, 7-6, 7-5, to advance to the third round of the $150,000 Italian Open at Rome.
In a pair of upsets, Isabel Cueto of West Germany surprised seventh-ranked Catarina Lindqvist of Sweden, 7-6, 6-4, and Aranxa Sanchez of Spain knocked off 10th-seeded Raffaella Reggi of Italy, 1-6, 6-2, 6-3.
In other matches, Mary Jo Fernandez downed Adriana Villagran of Argentina, 6-2, 6-3; Bettina Fulco of Argentina defeated Virginia Ruzici of Romania, 6-1, 6-1; Radka Zrubakova of the Soviet Union routed Catherine Suire of France, 6-1, 6-1, and Natalia Bykova, also of the Soviet Union, beat Janine Thompson of Australia, 7-5, 6-2.