Amazing Positions!

I came across the following recently, I thought it was interesting. And had never seen it before.

A defense perimeter is a drawing technique in which the side behind in material or otherwise at a disadvantage sets up a perimeter, largely or wholly composed of a pawn chain, that the opponent cannot penetrate. Unlike other forms of fortress, a defense perimeter can often be set up in the middle-game with several pieces remaining on the board.

I begin presenting a composed study with the theme:


W.E. Rudolph (La Strategie 1912)
White to move and force a draw.

White's has a material disadvantage, but forces a draw by giving up his remaining pieces to establish an impenetrable pawn chain. White draws with 1.Ba4+! Kxa4 (1...Kc4 2.Bb3+! Kb5 3.Ba4+ repeats the position) 2.b3+ Kb5 3.c4+ Kc6 4.d5+ Kd7 5.e6+! Kxd8 6.f5!


Now Black cannot break through White's pawn chain. His only winning chance is to place his rooks on b5, c6, etc. and hope that White captures them. White draws by ignoring all such offers.

Nice idea but couldn't happen in practice right? Wrong, the following actually happened in an OTB game:


A. Petrosian - L. Hazai
Schilde 1970

In this position, Hazai has a difficult endgame, since White can attack and win his a-pawn by force, and he has no counter-play. Black tried the extraordinary 45...Qb6!?, to which White replied with the obvious 46.Nxb6+? A mistake, Black should have carried out his plan of winning the a-pawn. 46...cxb6 Now Black threatens 47...h4, locking down the entire board with his pawns, so White tries to break the position open. 47.h4 gxh4 48.Qd2 h3! 49.gxh3 Otherwise 49...h2 draws. 49...h4! Black has established his fortress. White's can only breach the fortress by a queen sacrifice at some point (for example Qxa5 or Qxe5), but none of these give White winning chances as long as Black keeps his king near the centre. A draw was agreed within a few moves.

Here is the complete game:

Well I hope you enjoyed that, isn't chess amazing!