3...d6 4.d4: the passive defence is variation 5 of 6 in the Ponziani Opening course, a beginner opening course for White (ECO C44). It runs 15 moves and begins 1. e4 e5 2. Nf3 Nc6 3. c3 d6 4. d4 exd4 …. Black plays the solid 3...d6, but it is a bit passive. White takes the centre with 4.d4. After 4...exd4 5.cxd4 White has two central pawns, develops quickly and castles. In the lesson every move is explained on a board and then drilled; it is free.
Move by move
1. e4 – White takes the centre.
1... e5 – Black claims an equal share.
2. Nf3 – White develops and attacks e5.
2... Nc6 – Black defends e5.
3. c3 – The Ponziani. White prepares d4.
3... d6 – Solid but passive. It is a small inaccuracy, because White builds a big centre.
4. d4 – White takes the centre at once.
4... exd4 – Black gives up the centre. This is a small inaccuracy.
5. cxd4 – White takes back with the c-pawn and keeps two pawns in the centre.
5... Nf6 – Black develops and attacks e4.
6. Nc3 – White protects e4 and develops.
6... Be7 – Black gets ready to castle.
7. Bd3 – The bishop protects e4 and aims at the kingside.
7... O-O – Black castles.
8. O-O – White castles too. White has more space and an easy game.
chessGM