Maximum checking distance

4/30/2010 – This week ChessBase Magazine's endgame expert Karsten Müller analyses the endgame from Ghaem Maghami-Aleksandrov, played in the Dubai Open 2010. It is an instructive rook endgame in which the correct checking distance for the rook has an important role to play. Remember: when the pawns are on a single wing, generally speaking one extra pawn is not enough for victory, as long as the attacking pieces are not allowed to become too active. In the position in the diagram it is White's move and his task is to find a satisfactory defence (which he didn't). What would you recommend?