May 7, 1997
Chess | By ROBERT BYRNE
After Another Cautious Start, a Small Gamble Doesn't Help
In an attempt to pep up still another conservative opening against I.B.M.'s monster computer, Deep Blue, Garry Kasparov took a risk in the middle game yesterday. But it was a small one -- a speculative pawn sacrifice -- and in the end it did not succeed in steering Game 3 away from a draw.
DEEP BLUE/BLACK
KASPAROV/WHITE
Final Position.The world champion did get some advantage in mobility, but the machine knew how to put together a meticulous defense. When the situation looked threatening, Deep Blue ditched its material superiority to gain freedom of action for its pieces.
From one perspective, Kasparov did well to draw. Computers are famous for the miracles they can perform with a one-pawn advantage. But Kasparov surely did not see it that way.
Squirming in his chair and furrowing his brow, he was hoping to hoodwink the machine. But this hunk of hardware is proving stronger than it was a year ago when he first challenged it. The match is half over and he has not found a reliable way to tackle the complex inhuman opponent.
Kasparov, in his second turn as White, again chose a highly positional opening, the English, to stay away from the machine's strength..
The sequence with 9 Ng5 Bf5 10 e4 Bg4 11 f3 Bh5 drove the black queen bishop off to the side, but after 12 Nh3 Nd4, Deep Blue had obtained a well-posted knight that could not be driven out of the center by a pawn. The battle was even.
After 19 Bh3, Deep Blue refused to take a pawn with 19 . . . Bf3. Its grandmaster adviser, Joel Benjamin, thought that Kasparov would perhaps have gotten positional compensation by 20 Bd7 Bd1 21 Rd1 Nd7 22 Rb7.
After 22 gf, Kasparov had mobilized his kingside pawns, and after 22 . . . Qa5, he sacrificed a pawn with 23 Bd2!? Qa3.
After 25 f5, Deep Blue eliminated queens with 25 . . . Qd1 26 Bd1, but after 26 . . . Bh7, his queen bishop was almost a dead piece.
Deep Blue offered to return his extra pawn with 40 . . . Bc7 to relieve his cramped position and Kasparov accepted it with 41 Nc7 Rc7 42 Ra5. In the sequel, Kasparov agonized over the board, but could not find a way to break through the computer's defense and had to take a draw.
The computer's 25 .Ý.Ý. Be7!? and 26 .Ý.Ý. Bg5 represented a tricky change of front to create a pin of the white knight from another angle. The point, after 27 .Ý.Ý. a4 28 b4, was to create a brawl with 28 f5!?, but the computer could not play quietly and allow Kasparov to build up to a crushing position with Re2, Qe1 and Nf5.
Related Article
Kasparov Draws Third Game Against Deep Blue
Kasparov made the rook-for-bishop sacrifice with 30 f4!? Be2 31 fg, hoping to develop an attack against the enemy king.
But he soon chose to offer the exchange of queens with 34 Qf1 to prevent the black queen from becoming active and to use his connected g and f pawns in an endgame. And he was right. Despite Deep Blue's stubborn defense, Kasparov's pawn duo won the day. After 45 g7, there was no way to stop Kasparov from making a new queen, so Deep Blue's handlers gave up for it
Copyright 1997 The New York Times Company
