At last Black has covered the crucial 7th-rank-check threat and extricated himself from the mating net. Black now aims to trade off the Rs on the 7th rank, and the Q for the White N and R, giving him a passed-pawn+ endgame.

There is nowhere else for the White R to go.

White has no better; if he refuses the 'gift Q' then Black forces his way into the White position with ... Nf6 etc.

So, at last, we reach a Rubinstein-esque endgame. Black has a clear material and positional advantage with an extra passed pawn and an active K position.

This moves the Black K off the white diagonal to allow the c6- pawn to advance without offering White a B check on b7, and also prevents the White K from coming to f2-e2 etc. to try to cut off the c-pawn's advance.

With pawns on both sides of the board, the N is at a disadvantage against the B, as the N is a short-range piece whereas the B is able to reach both sides of the board. With these moves, however, Black eliminates his only weakness: by trading off the g and h pawns, the relative strength of the N and B is reversed.

With all of the pawns now on the same side of the board, the N is stronger than the B due to its ability to cover both colors. This is now an elementary win: either the B will have to be sacced for the c-pawn, or the N will shield the c-pawn from the B.

This scotches any drawing chances whereby the White K grabs the a5-pawn. Black now threatens ... Ne1 and ... Nd3 shielding the c-pawn's advance, or if White plays Bb1, then ... Ne1 and ... c2 forcing the B sac.

White falls on his sword.

White resigned. A terrific struggle which could have gone either way. 0-1