Chess Opening Theory/1. e4/1...Nf6/2. e5/2...Nd5/3. d4/3...d6

Alekhine's defence B02 Alekhine's defence 3...d6 Black threatens ...dxe5 and opens a line for their bishop to develop. White's next move makes a decision about how they would like to take back on e5 after ...dxe5. 4. Nf3 is the modern variation. This develops a piece and prepares to answer 4...dxe5, called the Larsen variation, with 5. Nxe5. In the main line, Black first pins the knight, 4...Bg4, and leaves the tension while both sides develop. Eventually White usually initiates the trade. 5. Be2 e6 6. O-O Be7 7. c4 Nb6 8. Nc3 O-O 9. Be3 Nc6 10. exd6 cxd6 + (see diagram). 4. c4 prepares to recapture with the f-pawn. After kicking the knight away, 4...Nb6, White plays 5. f4 (the four pawns attack) so they can meet 5...dxe5 with 6. fxe5 and keep three pawns in the centre. Alternatively, 5. exd6 cxd6 instead is the exchange variation (which may also be reached in the move order 1. e4 Nf6 2. e5 Nd5 3. c4 Nb6 4. d4 d6 5. exd6 cxd6). White controls the centre with the c- and d-pawns, and Black plays with ...g6, ...Bg7, etc. 4. f4!? is inaccurate because 4...dxe5 5. fxe5 c5!, and after 6. c4 the knight doesn't have to retreat to b6 but instead can route to b4 and later c6. Compare to the move order 4. c4 Nb6 5. f4 dxe5 6. fxe5, where Black's knight is already on b6 so 6...c5?! 7. d5 and the knight is very passive with only the d7 square left. 4. Bc4 is the Balogh variation. This commits White to recapturing on e5 with their d-pawn. Like 4. c4, 4. Bc4 attacks the knight but 4...Nb6 now comes with tempo on the bishop. 5. Bb3 dxe5 and White first plays the intermezzo 6. Qh5 (threatening 7. Qxf7#) e6 so that they unpin their d-pawn from their queen and can play 7. dxe5. If White initiates the trade of pawns, 4. exd6 cxd6, then 5. c4 Nb3 transposes into the exchange variation. This move order is a little inaccurate because, by trading the pawns first, White gives up control of f6, and 5...Nf6 is an option. 1. e4 Nf6 2. e5 Nd5 3. d4 d6 4. Nf3 Bg4 5. Be2 e6 6. O-O Be7 7. c4 Nb6 8. Nc3 O-O 9. Be3 Nc6 10. exd6 cxd6 Modern variation main line after 4. Nf3 Bg4 5. Be2 e6 6. O-O Be7 7. c4 Nb6 8. Nc3 O-O 9. Be3 Nc6 10. exd6 cxd6 1. e4 Nf6 2. e5 Nd5 3. d4 d6 4. c4 Nb6 5. f4 dxe5 6. fxe5 Nc6 7. Be3 Bf5 Four pawns attack main line after 4. c4 Nb6 5. f4 dxe5 6. fxe5 Nc6 7. Be3 Bf5 1. e4 Nf6 2. e5 Nd5 3. d4 d6 4. c4 Nb6 5. exd6 cxd6 6. Nf3 g6 Exchange variation main line after 4. c4 Nb6 5. exd6 cxd6 6. Nf3 g6. Theory table all 4. Nf3 Bg4 5. Be2 e6 6. O-O Be7 7. c4 Nb6 8. Nc3 O-O Modern variation +/++ 4. c4 Nb6 5. exd6 cxd6 6. Nf3 g6 Exchange variation 4. ... ... 5. f4 dxe5 6. fxe5 Nc6 7. Be3 Bf5 Four pawns attack 4. Bc4 Nb6 5. Bb3 dxe5 6. Qh5 e6 7. dxe5 Balogh variation References See also Alekhine's Defence