NEW YORK, OCT. 10 -- Defending champion Gary Kasparov tonight smashed one of his opponent's favorite openings in Game 2 of the world chess championship match here. The victory, so early in the 24-game match, gave Kasparov not only a 1 1/2- 1/2 lead over former champion and current challenger Anatoly Karpov, it also gave him a devastating psychological advantage.

Kasparov's opening move of king's pawn to e4 may have been a slight surprise for Karpov; the current champion has focused on the queen's pawn in building his opening repertory. But in a sense, Karpov invited Kasparov to use this opening. Karpov has been making a living on this Spanish variation playing black against the king's pawn for the past 10 years, and he used it successfully against Jan Timman in the candidates' final match earlier this year in Kuala Lumpur, Malaysia. Still, some of the games in that match showed that black could be put into an uncomfortable position, and Kasparov evidently took note of this during his preparation for the present match. He launched a violent assault on the fortress Karpov builds in this opening. With a victory on his first effort, he is likely to try to make this opening a theme of the match, at least in its early phase, and Karpov must either abandon it or find new wrinkles before Kasparov comes back with the white pieces in Game 4.

The opening, a variation on the Spanish Opening or Ruy Lopez, which dates back to the 16th century and has been analyzed in great depth, moved very fast at the beginning, with each player taking less than 15 minutes for the first 18 moves. Then the real game began; Kasparov's 19th move was played for the first time in history at the closely watched and deeply analyzed grandmaster level; the first 18 had already been played by a number of grandmasters and analyzed in various publications.

Before his new move, 19. f3, Kasparov had protected his pawn center and left his pieces free to maneuver to better squares. No counteraction in the center was possible for black, and Karpov had to sit tight (with waiting moves such as 22. ... Kh7) to see how Kasparov would use his space advantage. However, with 23. ... c6, Karpov weakened his queen's pawn, and this allowed Kasparov to create tactical possibilities around it. Karpov had a difficult decision after Kasparov's 24. Ng4. He could not exchange the knights because his rook pawn would be very vulnerable to attack by the queen, bishop and a rook on the opened file.

In one of the VIP rooms at the Hotel Macklowe, movie director Milos Forman, an avid chess fan, watched Karpov on a video screen thinking about this move. He suggested that Karpov should retreat with his knight, and as he made his suggestion, Karpov could be seen doing exactly that. This move, however, allowed Kasparov a combination based on a lot of knight forks and exploiting the weakness of the queen's pawn and the overload on the black bishop that had to protect pawns simultaneously on d6 and h6.

In his decisive combination, Kasparov had surrendered two minor pieces for a rook. Under normal circumstances, this material balance would favor Karpov, but black's pieces were so misplaced on the queenside that Kasparov was able to aim his forces directly at black's king. He made several strong moves starting with 30. Rd1, increasing his initiative step by step. After 33. f4, he was already dominating the game, and it was only a question of time before he would be able to break through. After 38. e5, his position was overwhelming, and his psychological advantage, due to Karpov's lack of time, increased formidably. (Each player has 2 1/2 hours for the first 40 moves and Karpov's clock had nearly run out.) Under heavy pressure, Karpov blundered his position away with 38. ... Nd5. Kasparov was able to win the exchange and the game was practically over.

Game 3 is scheduled to start at 5:30 p.m. Friday, with Karpov playing white.

Chess grandmaster Lubomir Kavalek contributed to this report.