Chess Opening Theory/1. e4/1...e5/2. Nf3/2...Nc6/3. Bb5/3...Nf6/4. O-O/4...Bc5/5. c3

Zukertort gambit Berlin defence, Beverwijk variation Classical defence, central variation C65 5. c3 · Zukertort gambit White leaves their e4 pawn undefended. Accepting with 5...Nxe4 increases the pressure on f2. If White plays inaccurately they are in trouble: 6. Re1?? allows either 6...Bxf2+! (7. Kh1 Bxe1 8. Qxe1 Nf6--- and Black is up four points of material) or 6...Nxf2! (7. Qa4 Nd3+ 8. Re3 Bxe3+ 9. dxe3 Nxc1---). White can try 6. d4 to obstruct the bishop, but their best reply is 6. Qe2, attacking the knight and eventually winning back the pawn or more. More common is to decline with 5...O-O, avoiding these complications. White continues 6. d4 and achieves a big centre with tempo. With White having now played c3, 5...a6? is a mistake. White's pawn on c3 now prevents Black's standard exchange Spanish rejoinder Qd4. 5...a6? 6. Bxc6 dxc6 7. Nxe4 and 7...Qd4 is not possible due to the pawn on c3. Theory table References See also Ruy Lopez