Touch-move rule the player touches his rook at the same time as touching the king, he must castle with that rook if it is legal to do so. If the player completes a two-square king move without touching a rook, the player must move the correct rook accordingly if castling on that side is legal. Otherwise, the move must be withdrawn and another king move made. When a pawn is moved to its eighth , once the player takes his hand off the pawn, a different move of the pawn can no longer be substituted. However, the move is not complete until
First-move advantage in chess whimsically suggests 17.h4!?, forcing Black to be the one to break the symmetry. 17... Re8! Rowson notes that this is a useful waiting move, covering e7, which needs protection in some lines, and possibly supporting an eventual ...e5 (see Black's twenty-second move). White cannot copy it, since after 18.Re1 Nxf2 Black would win a pawn. 18. Be3 Nxe5! 19. dxe5 Rc6! Rowson notes that with his more active pieces, "It looks like Black has some initiative." If now 20.Nxd5, Bxe5 "is at least equal for Black". 20. Nxb5 Bxe5! 20...Nxf2? 21.Qxd5! wins. 21. Nd4 Bxd4 22. Bxd4 e5 Rowson writes,