Tennis Roundup : Swedish Teen-Ager Kulti Surprises No. 6-Seeded Duncan, 6-3, 7-5

Nicklas Kulti, a 17-year-old Swedish junior star, upset No. 6-seeded Lawson Duncan, 6-3, 7-5, in the $425,000 Swedish Open tennis tournament Wednesday at Bastad, Sweden.

Kulti, ranked 398th in the world, dominated the match on the slow clay at the Bastad Tennis Stadium’s No. 1 court against Duncan, who was a finalist last Sunday in the U.S. Pro Championships at Longwood, Mass.

Top-seeded Joakim Nystrom of Sweden, who beat Wimbledon champion Stefan Edberg in last year’s Swedish Open final, rallied to defeat countryman Ulf Stenlund, 4-6, 6-2, 6-3, in another second-round match.

Unseeded Czech Karol Novacek became the first player to reach the quarterfinals by downing Thierry Tulasne of France, 6-1, 6-4, in the only third-round match.

Third-seeded Jan Gunnarsson of Sweden advanced to the third round with a 6-3, 7-6 win over Jean Fleurian of France.

Andre Agassi defeated Ricki Osterthun of West Germany, 6-3, 7-5, in a $350,000 Nabisco Grand Prix tournament at Stuttgart, West Germany.

The second-seeded Agassi needed 1 hour 46 minutes to eliminate the last West German remaining in the tournament.

In other second-round matches, third-seeded Brad Gilbert ousted Darren Cahill of Australia, 6-4, 7-6; Jonas Svensson of Sweden defeated Mansour Barhami of Iran, 6-3, 3-6, 6-0, and Kent Carlsson of Sweden eliminated Shozo Matsouka of Japan, 7-6, 6-4.

Angeliki Kanellopoulou of Greece upset second-seeded Katerina Maleeva of Bulgaria, 1-6, 6-4, 6-3, in the second round of the $75,000 women’s tournament at Brussels.

In other match matches, top-seeded Zina Garrison advanced to the quarterfinals with a 7-5, 6-4 victory over Celine Cohen of Swizerland; fifth-seeded Isabel Cueto of West Germany defeated Inmaculada Varas of Spain, 6-1, 6-0, and Silvia La Fratta of Italy beat Pat Medrado of Brazil, 7-5, 6-4.