Chess Board
[ECO code C43]
TRANSPOSITION
PETROFF DEF. (Steinitz Attack) to PHILIDOR DEF.
White's KKt and QP combined to attack Black's KP.
Black rejects ..KtxP or ..PxP lines but transposes into the Jaenish Counter-Attack line of Philidor's Defence, pushing his Queen's Pawn out to Q3(d6) to support his threatened KP and free his QB (though now blocking his KB). B-Alt.
     White  Black   Transp.White Black
 1.  P-K4   P-K4	  (1.)
 2.  Kt-KB3 Kt-KB3  (2.	Kt-KB3 P-Q3  )
 3.  P-Q4   P-Q3    (3.	P-Q4   Kt-KB3)
Continue: Transpose or Undo or Jump or Clear