16. ...  PxP
17.  BxKt PxB
18.  PxP

---------------------------------------
8 | #R |    |    |    |    | #R | #K |    |
|---------------------------------------|
7 | #P | #P | #P |    |    |    |    |    |
|---------------------------------------|
6 |    |    |    | #P | #P | #P |    | #P |
|---------------------------------------|
5 |    |    |    |    |    |    |    |    |
|---------------------------------------|
4 |    |    |    | ^P | ^P |    |    |    |
|---------------------------------------|
3 |    |    |    |    |    |    |    |    |
|---------------------------------------|
2 | ^P |    | ^P |    |    | ^P | ^P | ^P |
|---------------------------------------|
1 | ^R |    |    |    |    | ^R | ^K |    |
---------------------------------------
A    B    C    D    E    F    G    H

Diag. 130

In the end-game thus brought about the White Rooks have more freedom, as they can be mobilised easily on the third rank to act on either wing.  Black’s pawns, however, are stronger, being easily protected by the King, whilst White’s weak pawns at QR2 and QB2 are at too great a distance from the King; therefore White must see to it that Black does not open files for his Rooks on the Queen’s side.

18. ...  QR-B1 19.  QR-Kt1 P-Kt3 20.  KR-Q1 KR-Q1 21.  R-Kt3

White must now allow Black to occupy the QB or Q file.  After 21.  P-Q5 Black would simply play PxP; 22.  PxP, P-B3, with a certain draw.

21. ...  P-Q4
22.  R-Kt3ch

P-KB3 was the correct move here, in view of subsequent threats of mate.

22. ...  K-B2 23.  PxP RxP 24.  R-QR3 P-QR4 25.  P-KB4?

A mistake under time pressure, costing a pawn.  QR-Q3 was the move.

25. ...  P-QB4 26.  R-QB3 QR-Q1 27.  R-Kt1 RxP 28.  RxKtP RxP 29.  P-KR3 R-Q7 30.  R-Kt5

Not RxP, on account of R-B7, and the KKtP cannot be saved.

30. ...  R-(B5)B7 31.  R-KKt3 P-B4 32.  P-B4 P-B5 33.  R-KKt4 P-R4 34.  R-Kt5 RxP 35.  P-R4

Mate was threatened in a few moves through R-QB7-B8 and R(R7)-R8.

35. ...  R-(B7)Kt7

If now R-B7, White would win the KBP or obtain a perpetual check (36.  R-QKt7ch, followed by R-QKt8-KB8).  After the move in the text, White can still draw, as he wins back his pawn.

36.  RxR RxR
37.  RxRP?

This careless move now loses the game.  Of course White should have taken the BP.  If then P-R5, R-R5 held the pawn from behind, also after 37. ...  K-B3; 38.  RxQRP, P-K4, a draw would have been the result, as the White BP would soon have become threatening, e.g. 39.  R-R8, K-B4; 40.  P-B5, P-K5; 41.  P-B6, R-QB7; 42.  R-QB8, K-Kt5; 43.  P-B7, KxP; 44.  K-R2, P-K6; 45.  R-B8, RxP; 46.  RxPch, K-Kt4; 47.  R-K4, R-B6; 48.  K-Kt3, etc.; or 44.  R-K8, RxP; 45.  RxP, K-Kt6; 46.  R-K1, R-B7; 47.  K-R1, RxP; 48.  R-K3ch, and so on.