This knight is now the strongest piece on the board and it cannot be dislodged.
22. Ra3b3
White is mounting a minority attack against Black's queen-side, threatening to invade the Black position with Rb7 after exchanging pawns on b5.
22... Rf8e8
Seizing the open file, keeping White's king at bay.
23. Kg1f1 Re8e4
This looks aggressive, but merely wastes a tempo and accomplishes nothing; White's d-pawn is easily defended. Black should have played ...Re7 immediately, to hold the 7th rank against the coming White queen-side attack.
24. Bc1b2 f6
Clearing a path for the king to advance.
25. b5 Re4e7
The retreat of the rook is forced, otherwise the White rook invades the Black position.
