Ponziani Opening is a king’s pawn opening that starts with 1. e4 e5 2.Nf3 Nc6 3.c3 . White deviates from main alternatives like 3.Bc4 (Italian game) and 3.Bb5 (Ruy Lopez) with the idea to occupy maximum center with pawns and play d4 next move. However, main drawback of move 3.c3 is that it takes away the square for white’s b1 knight.
Black has three choices here. 3…Nf6 and 3…d5 are popular variations. 3…f5 is called Ponziani counter gambit.
Black plays 3…Nf6
With 3…Nf6 black attacks white’s e4 pawn which can’t be defended by Nc3 because the pawn occupies that square. Other moves like 4.d3, 4.Qc2 and 4.Bd3 don’t make much sense. White’s main continuation here is 4.d4
Now, if black captures 4…Nxe4, white shouldn’t capture directly with 5.dxe5. Instead white should go 5.d5 Ne7 6.Nxe5 Ng6 7.Qd4 Qf6 and after 8.Qxe4 Qxe5 9.Qxe5 Nxe5 10.Bf4 d6 11.Na3 a6 12.0-0-0 the game goes into endgame. The position is equal and neither side has much advantage. Therefore the result of the game will depend on a player’s endgame skills and positional play.
Back to move 4, if black captures 4…exd4, white should advance the other center pawn with 5.e5. After 5…Nd5 6.cxd4 Bb4+ 7.Bd2 Bxd2 8.Qxd2 d6 9.Nc3 dxe5 10.dxe5 black can play either 10…Be6 or 10…Nxc3 11.Qxc3 Qd5 with a good game.
Again, going back to move 4, black can decide not to capture any pawn in the center and simply defend the e5 pawn with 4…d6. Here, white can develop naturally with 5.Bd3 g6 6.0-0 Bg7 7.h3 and both sides have playable game.
Black plays 3…d5
After 3…d5, white’s best option is to play 4.Qa4, threatening to take Nxe5.
Here black has to know the opening theory, because intuitive natural moves don’t work here. For example something like 4…Nge7 obviously loses a pawn with 5.Nxe5. Also on 4…dxe4 5.Nxe5 white gets a better game.
Here black’s main move is simple 4…f6, defending the e5 pawn. It is important to remember this move because it doesn’t come naturally for most players. It looks like a move that you don’t want to play in the opening because firstly it weakens light squares and secondly it takes away a developing square for g8 knight. But in this position 4…f6 is perfectly fine.
After 5.Bb5 Nge7 6.exd5 Qxd5 7.d4, black can continue with 7…a6 8.Bc4 Qe4 with a good game or black can go 7…Bd7 8.0-0 e4 9.Nd2 f5 using his e and f pawns to occupy more space.
Back on move 4, black has other possibility which includes a pawn sacrifice. Instead of 4…f6, Black can play 4…Bd7. After 5.exd5 black has the tactical stroke 5…Nd4!. And after 6.Qd1 Nxf3 7.Qxf3 Nf6 8.Bc4 e4 9.Qe2 Bd6 black has a good compensation for the pawn. White’s queenside pawns will take a little time to develop and black has almost completed his development.
Black plays 3…f5
Finally, to really surprise white, black can play the Ponziani gambit with 3…f5. The idea is 4.exf5 e4 and by sacrificing a pawn black will get a few moves of natural development ahead with something like d5-Nf6-Bd6-0-0…etc.
Game played with Ponziani Opening
Here is a game played between Hou Yifan vs Magnus Carlsen
As we have seen, Ponziani opening is white’s attempt to trick the opponent into a sideline arising from king’s pawn opening. But black can defend well and have a great game by following simple opening principles and making moves with aim to control more of the center. The biggest drawback of move 3.c3 is that white’s queenside knight is robbed of its natural c3 square, and perhaps that is the reason that this opening becomes unattractive choice for white at top levels. Black can easily exploit this drawback by playing 3…Nf6 or 3…d5 and get a good game.