When I started playing chess seriously, I had the following stripped-down position with White against Paul Brown.

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I had captured on d5 to get a passed P. Paul played a nice combination, which was at the edge of my comprehension at the time:

[1]...Nb3 [2] axb3 Rxa1 [3] Rxa1

Nigel Fullbrook happened to pass by and saw the combination. Paul exclaimed exultantly, "Nigel, look as this!". After the combination had been played, Nigel remarked drily, "Too bad it loses," and sauntered away.

There is more than point count (Q=9=R+N+P) to chess: Nigel knew it, but Paul and I were less aware. I was amazed at how fast Paul's game fell apart, but <I> was the one with an extra piece to help push my passed d-pawn, and the P became unstoppable.

Needless to say, <FSR>'s analysis

< <FSR> wrote: 34...Bxc4 35.Rxb3 (35.Rxc4 Rxc4) axb3! 36.Qd2 Bxf1+ 37.Kxf1 Rxa3 must win for Black. Black has two rooks for a queen, and the passed b-pawn is a monster. >

As remarked in my follow-up post, 38. ♕b4 doesn't work. Black can reply with 38. ...♖a1 and either win the knight or force in the pawn.

The way you bring home the import of a passed...sublime! For most the impending loss of the Q would be a deterrent.

34...Bxc4 35.Rxb3 Bxd3 36.Rxd3 doesn't look very exciting.

34...Rxc4 35.Rxb3 and I don't see black will recover.

34...Qa2+ 35.Rf2 or 35.Rc2.

35 Qd2 Bxf8+

35 Qxc4 Qxc4

35 Rxc4 Qxd3 36 Nxd3 Rxc4 (Rxc8 Qxe4+ )

<35 Rxb3 axb3>

Black gives up his queen for Rook and Knight + a big passed pawn! Probably a good decision! Especially as the white queen is "en prise" and must move! So we have a <GOOT>. The queen only three escape squares b1, d2 and d1, but which is best?

<36 ? Rxf1+>
<37 Kxf1 Rxa3>

This is why this is a Saturday puzzle. There is still a lot to discuss, but whatever white plays as move 36 we will get to one of the following positions with white to move.

1) 36 Qb1

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2) 36 Qd1

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3) 36 Qd2

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From here white needs to formulate a plan to stop the loss of Ne1 which can easily be pinned against the king and the queen which is also in danger of being pinned.

But while there are still lots of defensive options for white it is worth noting that white has no chance of attacking black's back rank as Kf8 makes the black defenses rock solid. So any attempt to do so is just wasting moves.

So I would say that this cancels out option 3) 36 Qd2 as the only reason to play Qd2 is play Qb4 or Qb2 next and in either variation black quickly wins gets an advantage...

36 Qd2 Bxf8+ 37 Kxf8 Rxa3 38 Qb4 Ra1 39 Qxb3 Rcc1

36 Qd2 Bxf8+ 37 Kxf8 Rxa3 38 Qb2 Rca8 and none of the white's pieces can move and so the black knight will be freed to move up the board to help the rooks.

But to be honest I cannot see the killer blow. It all looks pretty easy for black, but there are too many options for my little brain...

~~~

Okay, so as suspected, I had the right first 4 moves for black, but not for white. White lost very quickly, so the only questions is

A) In any case, I gave 38. Ke2 (the game line) to Stockfish and fed it 38...Rca8. It gives a <-5.65/Depth of 21> evaluation of the position; making it clearly an objectively winning move.

Thankfully, as per Stockfish's output, Black can still resort to the ...Rb8 idea or even in some cases ...b2.

B) In the case of 38. Qb2 Rac8, as originally proposed by <Djoker> and <M.Hassan> (and the move I was actually looking at in the formulation of my solution post) Black preserves a whopping <-8.40/Depth of 24> advantage. Black is clearly just winning here just as in note 'A'.

C) As per the Qd2-b4 idea proposed by <Abdel Irada> as well as again <Djoker> in their solution posts (a move I did not look at in the formulation of my solution post), Stockfish confirms that the idea of 38. Qb4 Rac8 has practical winning chances value at <-2.82/Depth of 22>. This said, Stockfish much prefers 38...Ra1 here, as Abdel Irada himself stated in his follow-up post.

rookxb3 an axb3 (jive in boogy) on down in promo at b1 to queen at

rook stage any rally in white is bound to come unstuck as blacks

right in bxf1+ king has to recapture and rook comes crashing in a3

Here's crafty's defense and my refutation -- I think it's best. We follow the text until 38.Nd3 Rc2 39.Nc1 <Black to move and win>

White threatens 35.Rxb3.

Black has the opportunity of trading the queen for two rooks and creating a passed pawn with 34... Bxc4 35.Rxb3 (35.Rxc4 Qxd3 36.Nxd3 -36.Rxc8 Qa6- 36... Rxc4; 35.Qxc4 Rxc4 36.Rxb3 axb3, winning decisive material in any case) 35... axb3

A) 36.Qb1 Bxf1+ 37.Kxf1 Rab8

A.1) 38.Nd3 b2

A.1.a) 39.Nxb2 Rc3 40.Qa1 (40.Qa2 Rc2 - +) Rcb3 41.Nd1 Rb1 42.Qc3 Rxd1+ - +.

A.1.b) 39.Ke2 Rc2+

A.1.b.i) 40.Qxc2 b1=Q - +.

A.1.b.ii) 40.Kd1 Rh2 41.Ne1 Nc7 and White looks defenseless against Na6-c5-a4.

A.1.b.iii) 40.Ke1 Rh2 41.Kd1 Nc7 is similar to A.1.b.ii.

A.1.b.iv) 40.Kf1(3) Rc3 (trying 41... Rxd3 and 41... Rxa3, 42... Ra1) 41.Nxb2 Rcb3 - +.

A.1.c) 39.Ke1 Rc3 is similar to A.1.b.iv.

A.2) 38.Nc2 Rxc2 - +.

A.3) 38.Ke2 Rc1 - +.

B) 36.Qd2 Bxf1+ 37.Kxf1 Rab8

B.1) 38.Qb2 Rc3 39.a4 Ra3 40.a5 Rb2 41.Qb1 b2 42.Nc2 (42.Qxa2 b1=Q - +) 42... Rxa5 followed by Nc7-a6-c5 or Rc5-Rxc2 winning.

A) 39...Rb3 40. Qa2 Rcb8 41. Nc4 Rb1+ 42. Kg2.