Chess Board
[ECO code B01]
TRANSPOSITION
CENTRE COUNTER GAME to BIRD OPG. (Williams G.)
Black's QPawn directly challenged White's KP.
White advances his King's Bishop's Pawn to KB4(f4) offering a gambit pawn sacrifice by leaving his KP en prise (ie. in a position to be taken), and transposes into the Williams Gambit, a rare Bird Opening line that may yet become a KGD. W-Alt.
    White  Black    Transp.White Black
 1. P-K4   P-Q4	    (1.	P-KB4  P-Q4)
 2. P-KB4!?	    (2.	P-K4!?)
Continue: Transpose or Undo or Jump or Clear