Chess Board
[ECO code C43]
TRANSPOSITION
PETROFF DEF. to BISHOP'S OPG. (Urusov Gambit)
Black's QP (under QP+Kt attack) took White's QP.
White develops his King's Bishop to QB4(c4), leaving his KP undefended on purpose as a gambit (the Urusov by transposition). If 4..KtxP White has a compensating 5.QxP attack. W-Alt.
    White  Black    Transp.White Black
 1. P-K4   P-K4		  (1.)
 2. Kt-KB3 Kt-KB3   (2.	B-B4 Kt-KB3)
 3. P-Q4   PxP		  (3.)
 4. B-QB4	    (4.	Kt-KB3     )
Continue: Transpose or Undo or Jump or Clear