Benoni Defense

The Benoni Defense is a group of chess openings generally characterized by the opening moves 1. d4 c5 2. d5, although Black's ...c5 and White's answer d5 are often delayed. The most usual opening sequence for the Benoni is 1. d4 Nf6 2. c4 c5 3. d5. Black can then sacrifice a pawn by 3...b5 (the Benko Gambit), but if Black does not elect this line then 3...e6 is the most common move (though 3...d6 or 3...g6 are also seen, typically leading to main lines).

The Old Benoni starts with 1.d4 c5. The Old Benoni may transpose to the Czech Benoni, but there are a few independent variations. This form has never attracted serious interest in high-level play, though Alexander Alekhine defeated Efim Bogoljubow with it in one game of their second match, in 1934. The Old Benoni is sometimes called the Blackburne Defense, after Englishman Joseph Henry Blackburne, the first player known to have used it successfully.

In the Czech Benoni, also sometimes known as the Hromadka Benoni, after Karel Hromádka, Black plays 1.d4 Nf6 2.c4 c5 3.d5 e5. The Czech Benoni is much more solid than the Modern Benoni, but it is also more passive. The middlegames arising from this line are characterised by much manoeuvring, as White will, in most lines, play to gain space in the center and kingside, while Black looks to break with ...b7–b5 or ...f7–f5 after due preparation. Asa Hoffmann has played the line throughout his career, and produced an instructive game versus Zaderman.

The Modern Benoni usually begins after the moves 1.d4 Nf6 2.c4 e6 3.Nc3 (or Nf3) c5 4.d5 exd5 5.cxd5 d6 or 1.d4 Nf6 2.c4 c5 3.d5 e6 4.Nc3 (or Nf3) exd5 5.cxd5 d6. Then follows 6.e4 g6 7.Nf3 or 6.Nc3 g6 7.e4 (if Nf3 was played earlier). Obviously many transpositions are possible. The Modern Benoni is a risky attempt by Black to unbalance the position and gain active piece play, at the cost of allowing White a pawn wedge at d5 and a central majority. White usually plays for a central break with e5, while Black tries to effect ...b5. Black will fianchetto his king's bishop and castle on the kingside, playing for attack on the queenside with ...b7–b5 and in the semi-open e-file. Although it is not unknown for Black to play also on the kingside with, for example, a breakout with Nh5 in conjunction with f5, Fischer and Kasparov won famous games with this strategy against Boris Spassky and Viktor Korchnoi, respectively. White will play for a central initiative and simultaneously try to muzzle Black's counterplay.