Betsy Nagelsen took advantage of 17-year-old Susan Mascarin's inability to adjust her game today and won the $50,000 First National Bank Tennis Classic, 4-6, 6-0, 6-2, at the Towson Center.

Nagelsen, 25, won 10 straight games starting with the first game of the second set. She took a 4-0 lead in the deciding set by winning 15 consecutive points.

The 25th-ranked women's player in the world, Nagelsen showed some variety in her game while Mascarin, a Grosse Pointe, Mich., high school senior, showed none. Nagelsen aggressively took the net whenever possible, and at other times used soft touch shots.

"I knew I had to get in (to the net) eventually," said Nagelsen, who won $12,000, her biggest paycheck ever. "For me, it's foolish to try to hit the ball so hard. I just wanted to make the points last as long as I could until I could get the shots I wanted."

Mascarin, ranked 40th and known as one of the hardest-hitting ground strokers on the women's tour, tried to pass Nagelsen from the base line, but usually was wide. Although Nagelsen battled competitively when both were at the base line, it was not until the next-to-last game of the match that Mascarin attempted a drop shot. It was a winner.

"That's not my game," Mascarin said when asked if she considered varying her tactics during her poor run over the final two sets. "I just tried to fight my way out of it. There aren't many drastic changes I can make."

That drop shot was one of only three winners Mascarin hit in the third set. All the other points she scored were the direct result of Nagelsen errors.

Mascarin, who turned pro earlier this year, also collected her largest check ever, $10,000.

The eight-player tournament, for the benefit of the Junior League of Baltimore, suffered several setbacks concerning the biggest names it advertised. Martina Navratilova and Evonne Goolagong Cawley withdrew before the tournament began; Billie Jean King lost in the opening round to Mascarin, and top-seeded Andrea Jaeger defaulted to Nagelsen Saturday night because she became ill before the match.