Rushing the net with abandon, Henri Leconte, 19, today defeated Ivan Lendl, 6-2, 6-3, winning nine games in a row at one point to reach the quarterfinals of the $500,000 Tournament of Champions.

Leconte's domination was so complete that he lost only four points in his first seven service games. On only one occasion was Lendl able to reach break point.

Leconte said later that he patterned his game plan on the one John McEnroe had used in beating Lendl in the WCT finals Sunday in Dallas. Lendl and McEnroe are feuding, and two days ago Lendl flatly said he wouldn't have to worry about facing McEnroe in this Sunday's final because McEnroe wouldn't make it that far.

Instead, it was the defending champion and top seed who was beaten at the West Side Tennis Club in 62 minutes.

"He just played very well," Lendl said. "He didn't miss anything. He was serving well, he hit great approach shots and he was putting pressure on me. There was nothing more I can do. I did my best."

In another upset, Brad Gilbert beat fourth-seeded Kevin Curren, 6-4, 6-4. In three matches, Gilbert, 21, has yet to drop a set.

McEnroe, playing his first match of the tournament following a bye and a default, required only 67 minutes to defeat Jan Gunnarson, 6-1, 6-2. Gunnarson was able to hold serve only in the fourth game of the opening set and in the third and seventh game of the second set.

In Friday's quarterfinals, the second-seeded McEnroe will meet No. 10 Tomas Smid of Czechoslovakia, a 6-1, 6-1 winner over Scott McCain.

In other third-round matches, eighth-seeded Paul McNamee defeated No. 16 Jimmy Arias, 6-4, 3-6, 6-2, and No. 10 Tomas Smid routed Scott McCain, 6-1, 6-1.

Guillermo Vilas, the third seed, and ninth-seeded Johan Kriek also had nervous moments before joining 13th-seeded Leconte in the quarterfinals.

Vilas survived an opening-set tie breaker and came back from a 3-1 deficit in the second set to beat Mark Dickson, 7-6 (7-4), 6-3. Kriek survived two match points in beating Peter Bastiansen, 6-7 (7-9), 7-5, 6-1.

When they met in Houston last month, Leconte was up, 5-3, in the opening set and had a set point in the tie breaker before Lendl prevailed, 7-6, 6-3. The difference this time was that Leconte, a left-hander, was far more consistent.

"In Houston, he played two good games and one bad, two good games and three bad," Lendl said. "Here, from 2-2 he played without errors."