Chess Board
[ECO code C15]
FRENCH WINAWER DEFENCE
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
Example ends: Undo or Jump or Clear