rules, tactics, strategies and history

Sacrifice Example V

 Frequently a sacrifice is brought to maintain a pin which is bound to yield a piece in return sooner or later. The position of below is typical for cases of this kind.

								8
								7
								6
								5
								4
								3
								2
								1
a	b	c	d	e	f	g	h

Supposing Black plays

(1) ..., P-h6;
(2) B-h4, P-g5 to free himself of the pinning Bishop.

Then White can sacrifice the Knight f3 for the two black Pawns and thereby maintain the pin with the threat to regain the Knight immediately through Kt-d5. The ensuing play could be the following:

(3) Ktxg5, Pxg5;
(4) Bxg5, Bxc3;
(5) Pxc3.

Now White threatens to play P-f4 and Pxe5 opening the line of its Rook and thereby attacking the pinned Knight for the second time. This threat cannot be effectively countered. Black could try to unpin the Knight by

(5) .... K-g7;
(6) P-f4, Q-e8.

Indeed, Black saves its Knight in this way, but the exposed position of its King leads to a speedy disaster. For instance:

(7) Pxe5, Kt-h7;
(8) B-f6+, Ktxf6;
(9) Pxf6+, K-h7;
(10) Q-h5+, K-g8;
(11) Q-g6+, K-h8;
(12) Q-g7+/-.

Black could not take White's Queen on the 11th move because the Pawn f7 was pinned by the Bishop c4.

If Black had moved its King to g8 or g6 on the 8th move instead of taking the Bishop f6, White would have forced the mate by sacrificing its Rook on f5, thereby cutting off the Bishop c8 and giving its Queen access to the square g4.