Penetrate to the 7th rank with the rook
A rook on the 7th rank (the 2nd for Black) is a long-term endgame weapon. It ties down the enemy king to the back rank and grabs pawns laterally. When doubled rooks reach the 7th the position usually collapses for the defender. Tarrasch's old rule still holds: the rook belongs on the seventh.
Slide the rook along the 7th. It now attacks the a6 pawn and stays cutting off the king on the back rank. A rook on the 7th eats pawns laterally.
3 more clean runs (at any point) to reach Recall.
White to move. The rook is already on the 7th rank. Black has no rook to contest the file. The black king is pinned to its first rank by its own pawns.
3 more clean runs (at any point) to reach Recall.