Alekhine's Block
Alekhine's Block is the sacrifice of a piece on the 6th--or 3rd--rank, near the castled King, the idea being to break up the enemy's castled position and to block his defense at the same time. The most common form of this is when both sides are castled and your "f" pawn is gone and your Rook remains on "f1." If your enemy's Knight is at f6 you should consider an "Exchange Sacrifice" by giving up your Rook for his Knight. Whether or not this type of sacrifice would be successful depends on the board position. If you have additional pieces, especially the Queen, ready to strike, you would have a good chance at winning. Keep in mind that such a sacrifice may not necessarily always be accepted. Below are examples taken from actual tournament play. If you, the reader, has any furhter examples, either full games or diagrams please send them to me for possible publication.
Example 1
Sax-Sveshnikov Hastings 1977
Example 2
Alekhine-Wolf Bad Pistyan 1922
We have 2 additional online examples:
Example 3
Example 4