3...Bc5 4.d4: the big centre is variation 3 of 6 in the Ponziani Opening course, a beginner opening course for White (ECO C44). It runs 21 moves and begins 1. e4 e5 2. Nf3 Nc6 3. c3 Bc5 4. d4 exd4 …. 3...Bc5 is popular, but here it is a mistake. 4.d4 hits the bishop and White builds the ideal centre. After 6...Nf6 White pushes 7.d5 and gets the two bishops and lots of space. 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... Bc5 – Black copies the Italian set-up. Here it is a mistake, because d4 comes with tempo.
4. d4 – White attacks the bishop and builds the centre at once.
4... exd4 – Black takes the pawn.
5. cxd4 – White takes back with the c-pawn. Now White has pawns on d4 and e4.
5... Bb4+ – Black checks to gain time.
6. Nc3 – White blocks the check and develops a knight.
6... Nf6 – Natural, but an inaccuracy. Now White gains space with tempo.
7. d5 – White gains space and chases the c6 knight.
7... Bxc3+ – Black gives up the bishop to double White's pawns.
8. bxc3 – White takes back. The c3 pawn supports the centre.
8... Ne7 – The knight heads for g6.
The lesson goes on for 5 more moves, each with its explanation.
chessGM