Openings · C55–C59

Two Knights Defence

Counterattack rather than defend: 3…Nf6 hits e4 and dares White into 4.Ng5, the sharpest position in club chess.

1.e4 e5 2.Nf3 Nc6 3.Bc4 Nf6played as Black

The idea

Where the Giuoco Piano's …Bc5 develops quietly, …Nf6 asks a question. The critical answer is 4.Ng5, when Black must give up a pawn — 4…d5 5.exd5 Na5 — for a lead in development and lasting pressure. Nobody plays this opening for a quiet life.

It is the classical gambit test: material against time. Black is a pawn down for twenty moves in most lines and does not mind, because White's pieces are on bad squares and his king is still in the middle.

Practise the line

You play Black; the other side answers on its own. Nothing here is saved or graded.

Your move 1 of 30/3

1.e4e5
2.Nf3Nc6
3.Bc4Nf6

White is answering…

Common mistakes

Three that come up again and again below master level. Each is ordinary opening theory — a named trap, or the error every coach corrects — not a statistic, and not drawn from anybody's games.

The Fried Liver

1.e4 e5 2.Nf3 Nc6 3.Bc4 Nf6 4.Ng5 d5 5.exd5 Nxd5 6.Nxf7 Kxf7 7.Qf3+

The mistake: Recapturing on d5 with the knight.
Why it costs: 6.Nxf7 drags the king to f7 and 7.Qf3+ brings the queen with check. Black is not lost by force, but he is defending a king in the open for the rest of the game with no chance to castle, against an opponent who has known this line since he was ten.
Instead: 5…Na5, hitting the bishop and giving the pawn back later. It looks like a rim move and it is the main line for good reason.

The Traxler, played as a surprise

1.e4 e5 2.Nf3 Nc6 3.Bc4 Nf6 4.Ng5 Bc5 5.Nxf7 Bxf2+

The mistake: Meeting 4.Ng5 with the Traxler because it looks exciting, without having studied it.
Why it costs: It is a genuine piece sacrifice, and the difference between winning and losing runs eight or ten forcing moves deep from move five. 5.Bxf7+ — the quiet answer — is even more awkward for an unprepared Black than 5.Nxf7.
Instead: 4…d5, the main line, unless you have the Traxler written down. This is the one opening where playing from general principles does not work.

Chasing the pawn back

1.e4 e5 2.Nf3 Nc6 3.Bc4 Nf6 4.Ng5 d5 5.exd5 Na5 6.Bb5+ c6 7.dxc6 bxc6 8.Be2 Qd4

The mistake: Going after material once the compensation is in place.
Why it costs: 8…Qd4 wins a pawn and loses the initiative: 9.Nf3 hits the queen and White gets to develop with tempo — the exact commodity Black paid a pawn for. The gambit is only worth it while White is the one making awkward moves.
Instead: 8…h6 and 9…e4, driving the knight back and opening lines for the two bishops. Take the pawn back when it costs nothing, and not before.

Where it fits

The Two Knights Defence is a variation of the Italian Game, whose page covers the ideas this one takes for granted.

Try it on one of your own

The board above is for the line itself; this is for a game you played. Paste a game in this opening, or pull one from chess.com, and every move is graded against what the engine would have played. Open the board, read how the grading works, or go back to the other openings.