 (right-most diagram) Black has established his fortress, and now can draw by moving his king around.The only way White could attempt to breach the fortress would be a queen sacrifice at some point.In the remaining six moves of the game, Black shuffled his king between b7 and a7, where it would be well placed to deal with either a passed b-pawn (following Qxa5) or a passed d-pawn (following Qxe5).