Second-seeded Steffi Graf, who never had won a set from Martina Navratilova, overwhelmed her today, 6-2, 6-3, to win the $150,000 West German Women's Open Tennis Tournament.

Navratilova, the world's No. 1 player, cried after losing. She had won 31 straight matches. Graf, 16, a native of Heidelberg, West Germany, has won 20 straight, plus four straight tournaments.

She controlled today's entire match, which was played on clay before 5,500 fans at West Berlin's Rot-Weiss Courts.

Her forehands and passing shots were winners nearly every time Navratilova rushed the net.

"For me, she is still No. 1," Graf said after getting her check for $29,000. "I hadn't expected to win. She didn't play her best tennis, but I played my best tennis. I've had a lot of success recently but this is my most beautiful day."

Graf, ranked third in the world, broke Navratilova's serve twice to take a 3-0 lead in the first set, then expanded that to 4-1.

Graf moved in front, 5-2, by winning the seventh game with a well-placed lob to the farthest corner of the court and closed the set in 31 minutes.

She overcame a 3-1 deficit in the second set by breaking Navratilova and achieving a 3-3 tie with a sensational long-line hit that caused Navratilova to stop and applaud with the rest of the crowd.

Graf broke Navratilova for the fourth time to take a 5-3 lead in the second set.

Serving for the match, Graf went up by 40-15, netted a forehand but then ended the 64-minute match when Navratilova sent a forehand into the net.

Graf's recent streak has enabled her to reach peak form in time for the French Open, which will start next Monday.

She had played Navratilova three times. In their last previous match, in the Masters in New York March 22, she lost, 6-2, 6-2.

She hasn't lost a match since. She won the tournament in Hilton Head Island, S.C., by beating both Hana Mandlikova and the world's second-ranked player, Chris Evert.

Graf then won at Amelia Island, Fla., over West German Claudia Kohde-Kilsch, and in the U.S. Clay Courts in Indianapolis, over Gabriela Sabatini.

Navratilova, 29, cried as she received a check for $13,000 for her second-place finish.

"I am sorry I didn't play better, especially with my father and mother and my sister watching.

"It was over much too quickly. Steffi made so few unforced errors, I didn't expect that. My service was very inconsistent.

"I still need to be more aggressive on clay. I have to mix my shots more. But I learned something from my defeat and I'll know what I have to do if I meet her again in Paris."

Graf and Helena Sukova won the doubles final Sunday by defeating Navratilova and Andrea Temesvari, 7-5, 6-2.