The fortress or not ?

White on move

The question from chess reportage from Glasgow was, is this position fortress or not.

As you could probably assume an answer is not that simple.

I will provide some analysis in the chess viewer, but it could be very possible that analysis are not final word.

Before publishing these analysis I will explain position a little bit deeper with a help of some diagrams.

I should remind you that this discussion has a very little to do with the game, because it is mainly theoretical.

In the game it is impossible to foresee everything that I showed in analysis and without that one can trust his intuition.

The first thing would be to try to answer the question directly.

If I do so, I would say that this position is  the fortress.

What actually happened in the game is that both players made a mistake already at the beginning, but this do not have big influence on this theoretical question because the game soon transposed to the position which should be reached with best possible play.

That is why I will ignore this mutual mistakes and focus on main thing.

In order to keep his fortress unbreakable, Black has to find the whole series of only moves.

The main thing is that he should never take on f4 (well never in rational positions).

In this position which could be reached with best play from both players, and which was reached by transposition in the actual game, black needs to play only move:

42...Bc8!!

In my analysis I showed that every other move most probably loses the game.

So, what is the point of this mysterious bishop move.

Black needs to keep square e8 empty, and he needs to control square b7 at the same time.

In this position Black´s task is a bit easier, as he needs only to take a contact with square d6 (otherwise, white will take on e5 and play d5-d6. If Black takes with the king on e5 than White will win as in the game).

XX...Ke7!

Notice that Black´s bishop is on e8, but this is transformation of black´s defence since white´s knight moved from d3.

In the meanwhile White could try with some ideas like transfer his bishop to a2 but Black can successfully defend against that.

In this position White already tries for f4-f5 push.

There is a big dilemma for Black.

Take or f5 or not?

XX...Kf6! (or XX...Kf7!)

This has to be played.

As analysis shows, if he takes on f5 he will lose the game.

This can be critical point where White can try to do something better. Can he put his pieces somehow better in order to win the game after f4-f5 ? I did not find he solution, maybe you can.

This is especially hard moment for Black.

He needs to defend h5-pawn and he can do it with Nf6 and Ng7.

XX...Ng7!

Only this way, as I showed in analysis, Black is lost if he defend his pawn from f6. It is important to defend f5 square, not just the pawn on h5.

In this structure White needs to decide where he want to have his bishop before making next step.

He has option with bishop on d3 and e2.

White can force this position (with bishop on e2).

Black has to decide which piece will take on f5.

XX...Nxf5! (only this as XX...Lxf5 leads to piece sacrifice which should win for White XX.Bxb5)

And if black successfully managed to avoid all this nasty things he still has to make one more only move in bishop endgame.

This is explained on the next diagram.

I believe that White should jump on f5 with his bishop on e2, and that leaves Black more chance to fail.

If we go a little further with the position from previous diagram, we can reach this position. In fact, this is the best what White can achieve.

Black needs to make only move again.

XX...Bd7!

Without this, his position is lost.

I did not analysed this position deep enough but as I can see White´s only try is to play h4-h5 followed by Kh4.

If he do that, he can win.

Black needs to keep his king  near to g5. As I can see, there is no way to push his king away. In the moment when White plays h4-h5 Black should play his only move.

XX...Kg5!

Is it possible to prevent this, and to play Kh4?

White can manage to go with his king to h5 (in front of pawn) but I am not sure if that leads to something concrete.

This position can be reached if white checks on f5 with his bishop on d3.

He can now try with

XX. Be2

Black has three possibilities. Take on f5, and defend h5 with Kh6 or Be8.

XX...Be8!!

Only this move leads to a draw.

If Black can find all this moves, he would probably (as analysis shows at this point) save a day.

Does that means that White should try to find something better before he exchanged rooks?

Of course not.

A way for a draw is to complicated for practical play, and I think that the right estimation of this position at the very beginning would be good winning chances for White.

All details, with some fantastic variations you can find published in the chess viewer.
As I want to present analysis in clear form, I will divide  analysis in to parts.
First part is actual game and inferior defences by black.
The second part is analysis which starts with 42...Bc8!! .