White can tie Black up with 40.Bg6+ Kf8 (40... Kxg6 41.f5+; 40... Ke7 41.Rxe8+) 41.Kg3 and once the white king reaches a better square, the pawn ending after trading rooks and bishops is won for White:

A) 41... Re1 42.Kh4

A.1) 42... Re4 43.Kh5 Re3 44.Rxe8+ Rxe8 45.Bxe8 Kxe8 46.Kg6 Kf8 47.g5 hxg5 48.fxg5 fxg5 50.Kxg5 Kf7 51.Kf5 wins the d-pawn and the game.

A.2) 42... Re3 43.Rd8 (43.Kh5 Rxh3#) Re4 44.Kh5 transposes to A.1.

B) 41... f5 42.gxf5 Re1 43.Kg4 Re3 44.f6 (a curious stalemate arises after the not forced 44.Rxe8+ Rxe8 45.Bxe8 Kxe8 46.f6 gxf6 47.Kf5 Kf7 48.h4 h5) gxf6 45.Rxe8+ Rxe8 46.Bxe8 Kxe8 47.Kh5 Kf7 (47... Ke7 48.Kg6 Ke6 49.f5+ Ke7 50.Kg7 + -) 48.Kxh6 + -.

The first part is easy:

40.Bg6+!

A) 40...Kxg6? 41.f5+ Kf7 42.fxe6+ Ke7 43.Rxb6 and exchange+pawn gives white an easy win.

B) 40... Kg8 or Ke7 41.Rxe8+ wins.

C) 40... Kf8

The only defense - not much analysis is needed to reach this. Now white (though certainly not Larsen) might be tempted to cash in with 41.Bxe8? Rxe8 42.Rxb6, but black has 42... Re4 getting the pawn back immediately. However, there is no rush - black is nearly in zugzwang. King and bishop moves lose a piece, pawn moves are sacrifices, and the rook can't leave the e-file without losing a piece, so black now is confined to shifting the rook between e7 and e6. The 2nd stage is logic and a little bit of calculation. White wants to take the b-pawn under the most favorable circumstances possible. A triangulation maneuver could be considered by white (i.e. rook moves on 8th rank) to make the rook abandon the e-pawn, but I (and perhaps Larsen also) decided on the following direct method:

C.1) 41.h4! (to protect the bishop. f5 gives the black rook immediate access to e4.) Re7 42.h5 Re6 43.Kf3 (protects f4 and forces the rook to abandon defense of the b-pawn) Re1 44.Rxb6 Bxg6 (Rb1 45.Rb8 wins) 45.hxg6 Rb1 46.Rb8+

Now we reach a faniliar theme where white switches attention to the kingside pawns.

I think that the REAL point of White's play is that Black is in complete Zugzwang. (A few of you HAVE pointed this out.)

But as far as I can tell - and deep apologies if anyone already posted this, I am not trying to steal your thunder ... ... ...

The REAL point of Larsen's play is that he threatens to march his King to f5, swap off the Bishop and Rook, and then play Ke6, winning the K+P endgame easily?

Except, of course, that black is not in zugzwang at any point in the combination. Zugzwang, literally "oompulsion to move", is when one side has a perfectly satisfactory position but the fact that he is forced to move compels him to damage his position.

In today's puzzle, black is not forced to ruin his position by the compulsion to move. His problem is that he is so tied down that he cannot do anything while white improves his position.

40.Bg6+! (40...Kxg6?? 41.f5+);
The BK is forced on the back rank where it will remain extremely passive.

40...Kf8;
Forced.

41.f5!
This is the key manoeuvre that steals a crucial square on the e-file.

41...Re7;
Again, forced.

42.h4!
And B should resign as he has no more move that keeps the status-quo (42...h5 43.Bxh5 g6 Bxg6; 42...Re4 43.Bxe4 dxe4 44.Ke3).

Hopefully my calculation should prove accurate (this time!). Time to check!

-------

XD

I did but miserably failed to prove my point.

Analysis by Rybka 4 x64: depth 23:

1. (0.95): 34...b6 35.Rc8 Rxc8 36.Rxc8 Kf7[] 37.axb6 axb6[] 38.Rb8 Rd6 39.f5 Ke7 40.Kg3 Ba4 41.Rb7+ Kf8 42.Kf4 Rc6 43.Be2 Bb3 44.b5 Rd6 45.Rc7 Rd8 46.Bd3 Ra8 47.Rb7

Black.
(+3.29):39...Re6.
Best,
depth 23:

1. (2.01): 39...Ra7 40.Rxb6 Ke7 41.Rb8 Ra4 42.Ke3 g5 43.f5 Ra3 44.Kd2 Ra2+ 45.Bc2[] h5 46.gxh5 Bxh5 47.Rb7+ Kd8 48.Rb6 Be8 49.Kc3 Kc7 50.Rxf6 Bxb5 51.Bb3 Rh2 52.Rh6 Rf2 53.f6 Bc6

Yeah, black finds himself in what Soltis calls a "squeeze". He has moves, but they do nothing to prevent the opponent from steadily improving his position until finally a tipping point is reached.

When in real zugzwang, your position would be maintainable if you were not compelled to move.>

First, (and this happens all the time at our chess club), my ability to solve this problem was more due to memory than due to problem solving. WHY? I clearly remember that, while I was stationed in Iceland, I got the Eric Brondum book on Larsen. I practically memorized that book. Secondly, I have at least two more books (and one pamphlet) on Larsen. He is one of my favorite players. I have been over all the games in these books. So - if this game is in any those books, it was more a function of memory than problem solving.

Secondly, I called this Zugzwang, it was hardly a real case of Zug. (To me, Black was completely tied up.) However, I can see that you expect a master to be much more accurate than that. It was sloppy stuff, and maybe I somehow disappointed a few of you, maybe without even realzing it.

One thing I can tell you is that I NEVER intended for that post to sound high-handed or superior!!! I was just sharing my thoughts.

In fact, I have noticed a very weird trend lately. Some of the more difficult ideas, I get right away, (BUT NOT ALWAYS!!!); however, some days, with some of the really simple stuff, my mind does not grasp the pattern right away ... a few problems, I have spent a very long time on what you might have only taken a few minutes on. As to why this might be, I have no clue.