Positions with isolated passed pawns are easier to handle since they need the king’s assistance only up to the moment their common square includes the eighth rank! However, the outcome of the game depends to a great degree on how many files separate the white passed pawns. When pawns are separated by three files, then even a protected passed pawn on the third rank cannot save Black! In this study by Rauch, White to move wins although the common square of his passed pawns reaches only the seventh rank and his king must stay inside the square of the black strong protected g-pawn. The point is that Black’s king can only move along the d-file since the white pawns mutually protect each other i.e. if one pawn is captured, the other pawn will queen.