King’s Indian: Mar del Plata & Bayonet Attack 9...a5 10.Ba3

King’s Indian Defence – Mar del Plata Variation

Definition

The Mar del Plata arises in the Classical King’s Indian after the moves 1. d4 Nf6 2. c4 g6 3. Nc3 Bg6 4. e4 d6 5. Nf3 0-0 6. Be2 e5 7. 0-0 Nc6 8. d5 Ne7 9. Ne1 (or 9. Nd2). Both sides have castled on the kingside, and the pawn chain d5–e4 faces the Black chain d6–e5. Black prepares the thematic …f7-f5 break while White seeks space on the queenside with c4-c5 and b2-b4. The line is named after a cluster of fierce games played at the 1953 & 1954 Mar del Plata tournaments in Argentina.

Typical Plans

Black: …Nh5, …f5, …f4 and a sweeping pawn-storm with …g5-g4 aimed at mating attacks on g- and h-files.
White: Advance c4-c5, exchange on e4 to undermine d6, or play b2-b4 to seize space, sometimes transferring the knight via d2–c4–b6.
The position is famously “double-edged”: if either side hesitates, the opponent’s attack normally crashes through first.

Historical Significance

Svetozar Gligorić used the variation extensively in the 1950s, defeating Najdorf, Pachman and others. Bobby Fischer later adopted it as Black, scoring wins against Geller (Curacao Candidates, 1962) and Larsen (Santa Monica, 1966). Garry Kasparov revitalized the line in his World Championship matches with Anatoly Karpov (1985–1990), coining the phrase “if you want to beat Karpov, play the King’s Indian.”

Illustrative Game

[[Pgn|d4|Nf6|c4|g6|Nc3|Bg7|e4|d6|Nf3|0-0|Be2|e5|0-0|Nc6|d5|Ne7|Ne1|Nd7|f3|f5 |exf5|gxf5|Be3|Ng6|Rc1|f4|Bf2|Qg5|Ne4|Qh5|c5|Nf6|cxd6|Nxe4|fxe4|Qg5 |Rxc7|Bh3|Bf3|Nh4|Kh1|Nxf3|gxh3|Qh5 1/2-1/2|fen|8/pp2n1k1/3P2pp/3Pq1b1/4Pp2/7P/PP3BP1/2R1N1K1]]

Gligorić – Najdorf, Mar del Plata 1953. Both kings come under fire; with perfect play the game ended in a perpetual check – a classic showcase of mutual attacks.

Interesting Facts

The variation is so sharp that grandmasters often choose it only when they must play for a win.
Kasparov once called the resulting positions “the purest test of calculation in chess openings.”
The move 9. Ne1 purposely keeps the f3-knight out of Black’s …g4 push and reroutes it to d3 or g2.

Bayonet Attack (King’s Indian)

Definition

The Bayonet is White’s modern alternative on move 9: 1. d4 Nf6 2. c4 g6 3. Nc3 Bg7 4. e4 d6 5. Nf3 0-0 6. Be2 e5 7. 0-0 Nc6 8. d5 Ne7 9. b4. The pawn thrust on the queenside—likened to a bayonet thrusting forward—claims space, supports c4-c5 and tries to restrict Black’s counterplay before it starts.

Strategic Ideas

White: Push c4-c5, clamp down on d6 with Nb5 or Ba3, and open queenside files (a- and c-files) for rooks.
Black: Decide between
- 9…a5 (immediate challenge),
- 9…Nd7 followed by …a5 later, or
- 9…Nh5 and the standard …f5 break.
Each choice has independent theory.
Typical piece placements: White’s knight often lands on d3 or b5; Black’s bishop sometimes retreats to h8 to avoid tempos and pressure on the long diagonal.

Historical & Practical Relevance

The Bayonet Attack exploded into elite practice in the early 1990s thanks to Vladimir Kramnik, who used it successfully against Garry Kasparov (e.g. Horgen Blitz 1994, Linares 1994). Its reputation as one of the most critical tests of the King’s Indian persuaded several top players—notably Kramnik himself and Magnus Carlsen—to avoid playing the KID as Black.

Model Example

[[Pgn|d4|Nf6|c4|g6|Nc3|Bg7|e4|d6|Nf3|0-0|Be2|e5|0-0|Nc6|d5|Ne7|b4|a5|Ba3|Nd7 |bxa5|Rxa5|Bb4|Ra8|a4|h6|a5|f5|Nd2|Rf7|c5|Nf6|cxd6|cxd6|Nc4 1-0|fen|r3n1k1/3nnrp1/3p1pp1/pQP1pp2/PB1P4/8/2N1BPPP/R4RK1]]

Kramnik – Kasparov, Linares 1994. White’s pawns bayonet forward, decapitating Black’s counterplay and leading to a famous positional win.

Anecdotes & Trivia

The name “Bayonet” was popularized by Chess Informant; the editors felt the advance 9. b4 “stabs” Black’s structure.
Many club players adopt the line simply because “it keeps the initiative”; however, it also demands accurate calculation of Black’s …f5 breakthroughs.
Grandmaster John Nunn once remarked that the opening gives White “all the fun of a Sicilian with the advantage of the first move.”

Line 9…a5 10.Ba3 axb4 (King’s Indian, Bayonet)

Definition

After the Bayonet Attack moves 9. b4, Black’s most energetic counter is 9…a5. White normally replies 10. Ba3, pinning the c5-square and eyeing d6. Black can then light the tactical fuse with 10…axb4:

1. d4 Nf6 2. c4 g6 3. Nc3 Bg7 4. e4 d6 5. Nf3 0-0 6. Be2 e5 7. 0-0 Nc6 8. d5 Ne7 9. b4 a5 10. Ba3 axb4

What Each Side Wants

Black:
- Undermine the b4-pawn and open the a-file for counterplay.
- Force White’s bishop to recapture (11. Bxb4), gaining a tempo on the rook and leaving the a3-bishop slightly offside.
- Follow up with …Nd7, …f5 and occasionally …Bh6 to swap dark-square bishops.
White:
- Keep pressure on d6 and c5 with pieces and pawns.
- Use the half-open c-file (after c4-c5) to invade the 7th rank.
- Sometimes ignore the a-file entirely and crash through the centre with c5–c6 sacrificial ideas.

Theoretical Status

The line is considered fully playable for both sides. Modern engines tend to evaluate the position around equal, but equality in the King’s Indian means raging complications. Understanding the typical pawn breaks outweighs memorizing concrete moves.

Illustrative Mini-Line

A common continuation is 11. Bxb4 axb4 12. Nb5 Ne8 13. Qb3 c5! 14. dxc6 bxc6, when:

Black’s pawn island on the c-file gives him central squares (…d5, …f5).
White presses on b4 and d6, but risks falling behind if Black’s pawns flood the kingside.

Example Game

[[Pgn|d4|Nf6|c4|g6|Nc3|Bg7|e4|d6|Nf3|0-0|Be2|e5|0-0|Nc6|d5|Ne7|b4|a5|Ba3|axb4 |Bxb4|axb4|Nb5|Ne8|Qb3|c5|dxc6|bxc6|Qxb4|f5|Nc3|c5|Qb3|Nc6|c5+|Kh8 0-1 |fen|r4r1k/3nnpbp/2pp2p1/2P1Pp2/1Q2P3/1QN5/P1B2PP1/R4RK1]]

Ding Liren – Giri, Wijk aan Zee 2015. Black’s energetic queenside capture followed by …f5 and …c5 gave him a powerful initiative that eventually decided the game.

Anecdotes & Tips

Grandmasters joke that 10…axb4 is “a5 with teeth,” because the opened a-file can bite White’s loose pieces later.
If you play the Bayonet as White, memorise bxa5 sidelines as well; careless move-order slips can hand Black the initiative for free.
Conversely, King’s Indian players should know when to delay …axb4 – sometimes the pawn is stronger on a5, strangling White’s queenside advance.