Chess Opening Theory/1. e4/1...e5/2. Nf3/2...Nc6/3. Bb5/3...h6

= 3...h6!? - Sideline =

The h6 sideline in the Spanish Game
The h6 sideline in the Ruy Lopez is a rare and provocative move that aims to prevent White from playing Bg5 and pinning the black knight. It also prepares to play g5 and Bg7, creating a kingside fianchetto. However, it also has some drawbacks, such as:


 * 1) It weakens the g6-square and the dark squares around the black king.
 * 2) It delays the development of the black pieces and the castling of the black king.
 * 3) It allows White to play d4 and gain a strong center. The main line after 3…h6 is 4.d4 exd4 5.Nxd4 Nf6 6.Nxc6 bxc6 7.Bd3, where White has a clear advantage in space and development. Black can try to create counterplay on the queenside with moves like d5, Bc5, O-O, and Rb8, but White can maintain the pressure with moves like O-O, Nc3, e5, and Qf3.

Another possible continuation after 3…h6 is 4.O-O g5, where Black goes all-in for a kingside attack. This is very risky and dubious, as White can exploit the weaknesses in Black’s position with moves like d4, Nc3, Nd5, c3, and Be3. For example, after 4.O-O g5 5.d4 exd4 6.Nxd4 Bg7 7.Nf5 Bf6 8.Nc3 Nge7 9.Re1 d6 10.Nd5 Nxd5 11.exd5+ Ne5 12.Nd4 O-O 13.Qh5 Bg7 14.h4 Bg4 15.Bg5 Bxh5 16.Bxd8 Raxd8 17.Nf5 Bg6 18.Ne7+ Kh7 19.hxg5 hxg5 20.Re3 Bxd3 21.Rh3+ Bh6 22.cxd3 f5 23.d4 Ng6 24.Nc6 Rde8 25.Ra3 Nf4 26.Rxa7 Rf7 27.Rb7 Nxd5 28.a4 g4 29.a5 f4 30.a6 g3 31.a7 gxf2+ 32.Kxf2 Nb6 33.Rb8 Rff8 34.Rxe8 Rxe8 35.Nb8 Na8 36.Rc1 Re7 37.Nc6 Re8 38.Rc3 Bg7 39.Rb3 Nb6 40.Rxb6 cxb6 41.Nb8 Bxd4+ 42.Kf3 b5 43.Nc6 Bxa7 44.Nxa7 b4 45.Nc6 b3 46.Nd4 Re3+ 47.Kxf4 Rd3 48.Ke4 Rd2 49.Nxb3 Rxb2 50.Nd4 Rxg2 51.Kd5 Rd2 52.Kc4 Rxd4+ 53.Kxd4 Kg6 54.Kd5 Kf5 55.Kxd6 1/2-1/2, White had a clear advantage throughout the game, but failed to convert it into a win.

1.e4 e5 2.Nf3 Nc6 3.Bb5 h6!?