Finding right continuation is key to win

In the game which follows, White is in a commanding position well into the middle-game stages but fails to translate it into victory. White;s advantage slowly starts slipping and ultimately it is Black who emerges victorious.

White: Jonny Hector (2505) – Black: Igor Miladinovic (2565)
Sigeman & Co, Malmo 1998
Sicilian Defence
1.e4 c5
The Sicilian Defence
2.Nf3 e6 3.d4 cxd4 4.Nxd4 Nc6 5.Nc3 Qc7 6.Be3 a6 7.Bd3 Nf6 8.0–0 h5
White has already castled and Black rolls his pawn on the King side. Black also has the option of playing 8. ..Ne5
 9.h3 b5 Now he pushes his pawn on the queen side also. If 9...Bd6 10.Re1 (10.f4 Bc5 11.e5 Bxd4 12.Bxd4 Nxd4 13.exf6 gxf6 ) 10...Bh2+ 11.Kh1 Nxd4 12.Bxd4 Be5 13.Bxe5 Qxe5  
 10.Nb3 If 10.a3 Bb7 11.Qe2 h4 12.f4 Nh5 13.Qf2 Be7 14.Rad1 Rc8 had resulted in a victory for Black in a previous game
And if 10.Nxc6 Qxc6 11.a3 Bb7 12.Re1 h4
 10...Ne5 Now Black’s knight comes to the centre
 11.f4 White wants to immediately dislodge him
 11. ..Nc4 12.Bd4 If 12.Bc1 Bb4
 12...Bb7 If 12...Nxb2 13.Nxb5 axb5 14.Bxb2
 13.Qe2 h4 This looks interesting! If 13...Nxb2 14.Nxb5 axb5 15.Bxb2 Ba3 16.Bxf6 (16.Bxa3 Rxa3 17.e5 Nd5 18.Bxb5 Qb6+ 19.Kh1 Nc3) 16...gxf6 17.Bxb5 with White getting advantage And if  13...Rc8 14.e5 Nd5 15.Nxd5 Bxd5 16.a4 b4 17.f5
 14.a4 A strong pawn advance , challenging Black on the queen side
 14...Nxb2 15.axb5 Nxd3 16.cxd3
Also worth a look is 16.Qxd3
 16...axb5 17.Nxb5 Qd8
If 17...Qc6 18.Rxa8+ Bxa8 19.Ra1
 18.Qe3 If 18.Nc5 Rxa1 19.Rxa1
 18...Rxa1 19.Rxa1
Black is in a troubled state as he has not castled, his pieces are not developed and his other rook is virtually out of play
 19. ..Be7 20.Bb6 White on the other hand is piling on the pressure with his well posted pieces

 20...Qc8 If 20...Qb8 21.Bc7 Qc8 22.Nd6+ Bxd6 23.Bxd6
 21.Rc1 Bc6 If 21...Qb8 22.Bc7 Qa8 23.Bd6 where White is distinctly better
 22.Na7 If 22.Nc7+ Kf8 23.Na5 Ba3 24.Nxc6 dxc6 25.Rxc6 with Whhite in the driver’s seat 22...Qa8
Diagram 1
23.Na5 White’s pieces are moving at will!
23. ..0–0 Black finally gets to castle but by now it is too late!
24.N5xc6 dxc6 25.Nxc6 Ba3 26.Rc4  Rc8 27.Ne5 Nh5 If 27...Rxc4 28.Nxc4 Bb4 29.Bd4 28.Rxc8+ Qxc8 29.Nc4
White is preventing Black from infiltrating into his territory 29...Be7 30.f5 Ng3 31.fxe6 fxe6
If 31...Qxe6 32.Bc7
32.Bd4 Qb8 Threatening to invade and check the King
33.Nd2 If 33.Bb2 Qb3 34.Qf3 Qb4
33...Qb5 34.Qf3 Bc5
If 35.Bf2 Qb6 35...Qxc5+ 36.Qf2 Qc1+ 37.Nf1 If 37.Kh2 Qh1 checkmate And if 37...Qxd2 38.Qxd2 Nf1+
37...e5 38.Qf3
If 38.Qa2+ Kh7 39.Qf2 .Qd1 (39...Kg6 40.Qf3) 40.Qf7 Qe1 41.Qf8 (41.Qf2 Ne2+) 41...Ne2+ 42.Kh2 Nf4 43.Kg1 Qe2 44.Qf5+ Kh6 45.Qg4 Qxg4 46.hxg4 Nxd3]
38...Qe1 39.d4 exd4 40.e5 Qxf1+ 41.Qxf1 Nxf1  If 41...Nxf1 42.Kxf1 Kf7 43.Ke2 Ke6 44.Kd3 Kxe5
And White resigned.
Diagram 2
White to play and win
 1.Nb6+ cxb6 2.Be6 Qxe6 and White wins.