Chess Opening Theory/1. e4/1...e5/2. Nf3/2...Nc6/3. Bb5/3...Nd4/4. Nxd4/4...exd4/5. Bc4

Bird's defence Bird's defence C61 5. Bc4 In this Bird's defence sideline, White delays castling to move their bishop onto the a2-f7 diagonal. This renders Black's usual turn five options, 5...c6 or 5...Bc5, less effective. 5...c6 no longer comes with tempo, and 5...Bc5 runs into a serious trap. After 5...Bc5? White can sacrifice the bishop on f7, then recover Black's bishop by forking it with their queen. After 6. Bxf7+ Kxf7 7. Qh5+ g6 8. Qxc5 (all forced) Nf6 9. Qxd4+++, White has won two pawns. 5...Nf6 is the main move. This develops the kingside and attacks e4. White's usual developing move to defend it, Nc3, is unavailable due to the enemy pawn on d4. It looks like White must waste time with a non-developing move to defend it, but they can actually 'gambit' it with 6. O-O, knowing they can recover it shortly. 6...Nxe4 7. Bxf7+ (7. Re1?! allows 7...d5 to secure the knight) Kxf7 8. Qh5+ g6 9. Qd5+ Kg7 10. Qxe4 and White recovers the pawn and trades a bishop for a knight. 5...c6 can be played anyway, but as it no longer comes with tempo it is less inviting. White can castle 6. O-O and it transposes to 5. O-O c6 6. Bc4. Theory table 0 5...Bc5? 6. Bxf7+ Kxf7 7. Qh5+ g6 8. Qxc5 Nf6 9. Qxd4 +++ Bird's defence 5...Nf6 6. O-O Nxe4 7. Bxf7+ Kxf7 8. Qh5+ g6 9. Qd5+ Kg7 10. Qxe4 5...c6 6. O-O d5 7. exd5 cxd5 8. Bb5+ Bd7 9. Re1+ Ne7 10. c4!for an example game, see Kasparov v Khalifman, 2002 + References See also Ruy Lopez Reimagining 1.e4: Cunning, Crafty & Concise Ntirlis Nikolaos Quality Chess 2024 978-1-78483-243-8 209-211