Deep Blue versus Garry Kasparov was a pair of famous six-game Human-computer chess matches played between the IBM supercomputer Deep Blue and the World Chess Champion Garry Kasparov. The first match was played in February 1996 in Philadelphia, Pennsylvania. Kasparov won the match 4–2, losing one game, drawing in two and winning three. A rematch, which has been called "the most spectacular chess event in history", was played in 1997 – this time Deep Blue won 3½–2½.

Here are the result summaries of the matches. The winner is denoted with bold text, in addition to the 1–0 format result.

The 1996 match

Game #	White	Black	Result	Comment
1	Deep Blue	Kasparov	1–0
2	Kasparov	Deep Blue	1–0
3	Deep Blue	Kasparov	½–½	Draw by mutual agreement
4	Kasparov	Deep Blue	½–½	Draw by mutual agreement
5	Deep Blue	Kasparov	0–1	Kasparov offered a draw after the 23rd move.
6	Kasparov	Deep Blue	1–0
Result: Kasparov – Deep Blue: 4–2

The 1997 rematch

Game #	White	Black	Result	Comment
1	Kasparov	Deep Blue	1–0
2	Deep Blue	Kasparov	1–0
3	Kasparov	Deep Blue	½–½	Draw by mutual agreement
4	Deep Blue	Kasparov	½–½	Draw by mutual agreement
5	Kasparov	Deep Blue	½–½	Draw by mutual agreement
6	Deep Blue	Kasparov	1–0
Result: Deep Blue–Kasparov: 3½–2½

The 1996 match

1996 Game 1, Deep Blue vs. Kasparov

The first game of the 1996 match was the first game to be won by a chess-playing computer against a reigning world champion under normal chess tournament conditions, and in particular, normal time controls.

The game was played on February 10, 1996.

1996 Game 2, Kasparov vs. Deep Blue

The second game began with the Open Catalan Opening. Kasparov played in what could be called a preemptive style blocking all Deep Blue's development tries. The game lasted for 73 moves but eventually Deep Blue's operator had to resign the game for the computer in a position where both players had a bishop but Kasparov had three pawns against Deep Blue's one.

The game was played on February 11, 1996.

1996 Game 3, Deep Blue vs. Kasparov

In the third game Kasparov played the Sicilian Defence to which Deep Blue responded with the Alapin Variation. The game lasted for 39 moves and was drawn.

The game was played on February 13, 1996.

1996 Game 4, Kasparov vs. Deep Blue

The fourth game was the second game to end in a draw, even though at one point Deep Blue's team refused Kasparov's draw offer. The opening played was the Semi-Slav Defense.

The game was played on February 14, 1996.

1996 Game 5, Deep Blue vs. Kasparov

The fifth game was the turning point in the match. During the game, Kasparov, playing black, chose a different opening, the Four Knights Game, from the Sicilian Defence he had played in games one and three and came on top. This was particularly embarrassing for the Deep Blue team, because they had declined Kasparov's draw offer after the 23rd move. This one is the only game in the match that black won.

The game was played on February 16, 1996.

1996 Game 6, Kasparov vs. Deep Blue

In the end of the sixth game, Deep Blue had its pieces crammed into the queen side corner, almost completely unable to defend its king. Deep Blue resigned, because it was losing so badly. Kasparov's next move would probably have been 44.Qe7 to exchange the queens. That would have allowed his pawn, which was about to promote, to advance.

The game was played on February 17, 1996.

1.Nf3 d5 2.d4 c6 3.c4 e6 4.Nbd2 Nf6 5.e3 c5 6.b3 Nc6 7.Bb2 cxd4 8.exd4 Be7 9.Rc1 O-O 10.Bd3 Bd7 11.O-O Nh5 12.Re1 Nf4 13.Bb1 Bd6 14.g3 Ng6 15.Ne5 Rc8 16.Nxd7 Qxd7 17.Nf3 Bb4 18.Re3 Rfd8 19.h4 Nge7 20.a3 Ba5 21.b4 Bc7 22.c5 Re8 23.Qd3 g6 24.Re2 Nf5 25.Bc3 h5 26.b5 Nce7 27.Bd2 Kg7 28.a4 Ra8 29.a5 a6 30.b6 Bb8 31.Bc2 Nc6 32.Ba4 Re7 33.Bc3 Ne5 34.dxe5 Qxa4 35.Nd4 Nxd4 36.Qxd4 Qd7 37.Bd2 Re8 38.Bg5 Rc8 39.Bf6+ Kh7 40.c6 bxc6 41.Qc5 Kh6 42.Rb2 Qb7 43.Rb4 1-0

The 1997 rematch

1997 Game 1, Kasparov vs. Deep Blue

The 1997 rematch began with the King's Indian Attack, which led Kasparov to victory in 45 moves.

This game was played on May 3, 1997.

1997 Game 2, Deep Blue vs. Kasparov

In this game Kasparov accused IBM of cheating, a claim repeated in the documentary Game Over: Kasparov and the Machine. Kasparov eventually resigned, although post-game analysis indicates that the game could have been drawn. The game started with the Ruy Lopez opening Smyslov Defence variation.

This game was played on May 4, 1997.



Kasparov missed the fact that after 45... Qe3 46.Qxd6 Re8, black can force a draw by perpetual check. His friends told him so the next morning. They suggested 47.h4 h5!, to result in a quick ending. The reference does not mention 47.Qc7+ (or Qd7+) as a way for white to further delay the drawn ending.

The game became subject to a forced draw instead of a probable win for Deep Blue when it moved 44.Kf1 instead of an alternate move of its king. Regarding the end of game 2 and 44.Kf1 in particular, chess journalist Mig Greengard in the Game Over film states, "It turns out, that the position in, here at the end is actually a draw, and that, one of Deep Blue's final moves was a terrible error, because Deep Blue has two choices here. It can move its king here or move its king over here. It picked the wrong place to step." Another in that film, four-time US champion Yasser Seirawan, then concludes that, "The computer had left its king a little un-defended. And Garry could have threatened a perpetual check, not a win but a perpetual check."

1997 Game 3, Kasparov vs. Deep Blue

The third game was interesting because Kasparov chose to use an irregular opening, the Mieses Opening. He believed that by playing an esoteric opening, the computer would get out of its opening book and play the opening worse than it would have done using the book. Although this is nowadays a common tactic, it was a relatively new idea at the time. Despite this anti-computer tactic, the game was eventually drawn.

This game was played on May 6, 1997.

1997 Game 4, Deep Blue vs. Kasparov

In this game Kasparov played the Caro-Kann Defence. Later on he had time problems and had to play in hurry, as both players had two hours for the first 40 moves and Kasparov was approaching his time limit. The sub-optimal moves he played in hurry may have cost him the victory.

This game was played on May 7, 1997.

1997 Game 5, Kasparov vs. Deep Blue

In this game, the King's Indian Attack opening was played. Like in the previous game, the Deep Blue played a brilliant endgame that secured a draw, when it was looking like Kasparov would win.

This game was played on May 10, 1997.

1.Nf3 d5 2.g3 Bg4 3.Bg2 Nd7 4.h3 Bxf3 5.Bxf3 c6 6.d3 e6 7.e4 Ne5 8.Bg2 dxe4 9.Bxe4 Nf6 10.Bg2 Bb4+ 11.Nd2 h5 12.Qe2 Qc7 13.c3 Be7 14.d4 Ng6 15.h4 e5 16.Nf3 exd4 17.Nxd4 O-O-O 18.Bg5 Ng4 19.O-O-O Rhe8 20.Qc2 Kb8 21.Kb1 Bxg5 22.hxg5 N6e5 23.Rhe1 c5 24.Nf3 Rxd1+ 25.Rxd1 Nc4 26.Qa4 Rd8 27.Re1 Nb6 28.Qc2 Qd6 29.c4 Qg6 30.Qxg6 fxg6 31.b3 Nxf2 32.Re6 Kc7 33.Rxg6 Rd7 34.Nh4 Nc8 35.Bd5 Nd6 36.Re6 Nb5 37.cxb5 Rxd5 38.Rg6 Rd7 39.Nf5 Ne4 40.Nxg7 Rd1+ 41.Kc2 Rd2+ 42.Kc1 Rxa2 43.Nxh5 Nd2 44.Nf4 Nxb3+ 45.Kb1 Rd2 46.Re6 c4 47.Re3 Kb6 48.g6 Kxb5 49.g7 Kb4 1/2-1/2

If White plays 50 g8=Q then Black can force a draw by threefold repetition, starting with 50... Rd1+ and then 51... Rd2+.

1997 Game 6, Deep Blue vs. Kasparov

Before the sixth match the overall score was even: 2½–2½. Kasparov played, uncharacteristically, the Caro-Kann Defence. He then allowed Deep Blue to commit a knight sacrifice which wrecked his defences and forced him to resign in less than twenty moves.

This game was played on May 11, 1997.

1.e4 c6 2.d4 d5 3.Nc3 dxe4 4.Nxe4 Nd7 5.Ng5 Ngf6 6.Bd3 e6 7.N1f3 h6 8.Nxe6 Qe7 9.O-O fxe6 10.Bg6+ Kd8 11.Bf4 b5 12.a4 Bb7 13.Re1 Nd5 14.Bg3 Kc8 15.axb5 cxb5 16.Qd3 Bc6 17.Bf5 exf5 18.Rxe7 Bxe7 19.c4 1-0

See also

• List of chess games

References

Notes

Further reading

• Arimaa - A game inspired by Karparov's loss to Deep Blue in 1997.