kingside pawn structure. The idea is to eventually counterattack on the g1–a7 diagonal with a move like ...Qb6, preventing White from castling. An example line would be 6...g6 7.Nf3 Bg7 8.a4 Nc6 (note 8...Nc6 as opposed to the usual Najdorf ...Nbd7, as c6 is a more flexible square for the knight with a queen on b6) 9.Bd3 Qb6. Adams Attack: 6.h3 Introduced by Weaver Adams during the middle of the twentieth century, this odd-looking pawn move has mostly been used as a surprise weapon to combat the Najdorf. Should Black continue with 6...e5 anyway, White can respond with 7.Nde2 following up with g4 and Ng3, fighting for the weak light squares by playing g5. It is thus recommended that Black prevents g4 altogether with 7...h5. Black can also employ a Scheveningen setup with 6...e6 followed by 7.g4 b5 8.Bg2 Bb7, forcing White to lose more time by defending the e4-pawn, since ...b4 is a threat. It was not until early 2008 that an answer to Black was finally found. After 9.0-0 b4, White has the positional sacrifice 10.Nd5!, which gives Black long-term weaknesses and an open e-file for White to play on. Since then, it has been popular on all levels of play. Other sixth moves for White Beside the main lines mentioned above White has other options: 6.f3, 6.g3, and 6.a4 are less common, but are also respected responses to the Najdorf. Moves such as 6.Bd3, 6.Qf3, 6.Rg1 (the Petronic Attack), 6.Nb3, 6.a3, 6.h4, 6.Qe2, and 6.Qd3 are rarely played, but are not so bad and may be used for surprise value. Other rare moves include 6.g4, 6.Nf3, 6.b3, and 6.Bd2. Notable games Shakhriyar Mamedyarov vs Boris Gelfand. 0-1. Candidates (2011), Kazan. Fischer-Sozin Attack: Flank Variation. After various sacrifices, Gelfand has six extra pawns for a rook. Sergey Karjakin vs Viswanathan Anand. 0-1. Corus Group A (2006), Wijk aan Zee. English Attack. Anand sacrifices a knight and a bishop and Karjakin resigns with checkmate unstoppable. Michael Adams vs Garry Kasparov. 0-1. Linares (2005). English Attack. Both players attack simultaneously and Kasparov claimed later that it was important to let his opponent think he was winning. Wolfgang Unzicker vs Robert James Fischer. 0-1. Varna Olympiad Final-A (1962). Classical/Opočenský variation. A nineteen year old Fischer outplays his opponent in a more positional line. See also List of chess openings List of chess openings named after people References Works cited Further reading