Chess Board
[ECO code A42]
PILLSBURY DEFENCE
Exchange Variation
White's QP removed Black's challenging KP in the centre and threatened his QP on Q6(d6).
Black's own QPawn exchanges, taking the newly doubled KP on K4(e5) to free his KB diagonal and leave his queen en prise, for 4.QxQ+ch..KxQ to keep equality at the expense of losing castling rights.
	White	Black
 1.	P-Q4	P-Q3
 2.	P-QB4	P-K4
 3.	PxP	PxP
Example ends: Undo or Jump or Clear