Chess Board
[ECO code C15]
The Fingerslip Variation

Black developed his king's bishop to pin White's QKt, ending support for White's KP on K4(e4).
White develops Queen's Bishop to Q2(d2) halving the pin. Alekhine called it a "lapsus manus" after a game Alekhine-Flohr, Nottingham 1936. W-Alt.
	White	Black
 1.	P-K4	P-K3
 2.	P-Q4	P-Q4
 3.	Kt-QB3	B-Kt5
 4.	B-Q2

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