Tensiones de paso, contacto y metal-metal

W

hen I saw the analyses by Artu r Yusupov in the previous chapter I was reminded of several studies on the same theme, which in their time made a strong impression on me. I hope that they will also appeal to you . Their beauty l ies in the unusual amount of work carried out by the white knight, the paradoxical manoeu­

vres of the white pieces, and above all the precision and depth of logic behind these manoeuvres.

Before enjoying the solutions, try to find the answers yourself. I should warn you before­

hand: the problems are very difficult, and you will most probably have to move the pieces on the board (perhaps only the second example might be solved in you r head ). But even so, don't b e in a hurry to make moves - first reason to yourself about the final and intermediate aims of both sides, the plans they will carry out, any important intermediate positions, and so on.

N. Grigoriev 1 932

A knight can stop a rook's pawn, if it succeeds in 'touching' any square in its path (apart from the corner square h1). In the given instance it is clear that the knight will aim for the h2-square. How to reach it­

seeing as the black king stands in its way?

Here are some logical considerations, which will make it easier to find the solution. The knight can reach h2 via g4 or f1 . Each of these routes can be controlled separately by the black king. It is necessary to create a 'double attack' - by threatening to go to h2 by both ways. The knight can reach f1 via d2, and g4 via e5. Do you see the intersection point of these two routes?

1 tt'lb4! h5

2 tt'lc6!

Not 2 tt'ld5+? 'itof3 ! , and the pawn cannot be stopped . Note that a king restricts a knight most effectively when there is one square between them along a diagonal, or two squares between them along a rank or a file.

2 ... 'it>e4!

Of cou rse, not 2 . . . h4? 3 tt'le5, when the g4-square can be covered only by 3 . . . Wf4 , but then there follows 4 tt'lg6+.

3 tt'la5!!

Only in this way can the knight reach the key c4-square, from where it can aim for both f1, and g4 . 3 tt'ld8? would have lost after 3 . . . h4 4 tt'le6 'it>f5! 5 tt'ld4+ 'ltog4 .

3... h4

4 tt'lc4!

4 tt'lb3? �e3 .

4 ... 'itof3!?

More about the 'Montaignian' Knight

lLJ

_{1 09} variation he is able to deflect the knight from its route to h2, and, as you can see, 'touching' the h 1 -square with the knight does not help White.

5 . . . 'it>g3

Forced: the g4-square must be guarded , but if 5 ^.. . 'it>f4, then 6 ltJg6+.

In conclusion I should mention that 2 lZ'lc2+?

(instead of 2 lZ'lc6+ ! ) would be justified after 2.. .'it>e4? 3 lZ'la3! 'itd3 (3 . . . h4 4 ltJc4) 4 'it>b5!

and lbc4, but 2 .. .'�f2! leads to a win .

D . Gurgenidze 1 970

This study is a n a rtistic adaptation of a position by Nikolai Dmitrievich Grigoriev.

The threat of win n i ng the kn ight is easily parried by approaching the b5-pawn with the

king: 1 ..t>b3(a3) 'it>f7 2 'it>b4 'it>g7 3 'it>xb5 'it>xh7 4 'it>c4, and the king enters the square of the h-pawn. What, then , is the problem?

It turns out that Black can save a very important tempo by avoiding the attack on the knight and satisfying h imself with merely restricting its mobility: 1 .. .<.t?e6! 2 'it>b4 'itf5 3 'it>xb5 h5, and the pawn queens. This means that i n reply to 1 . . . 'it>e6 White must immedi­

ately tackle the h-pawn with his knight.

In a practical game without much hesitation many players would play 1 'it>b3 'it>e6 2lZ'!f8+

'it>f5 3 ltJd7 h5, and only now think about

This is why it is important to calculate all the variations as early as the first move - the b3-square must be left free for the white knight.

5 lZ'ld3? would have lost after 5 . . . h3 6 lZ'lf2 order to create difficulties for the opponent.

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More about the 'Montaignian' Knight

R. Reti, ^A. Mandler 1 924

We find the square c2. From here the knight takes away the important e3-square, and it is itself invulnerable in view of the reply 'i!te2.

The black king has to be at d2 or d 1 . But with the king on d1 White has the decisive tt'lb4!

followed by tt'ld5. It is clear that here we begin to have mutual zugzwang positions.

Black has to play accurately from the very start. 1 . . . 'it>d3? is bad in view of 2 tt'lf3 'i!te3 3 tt'le 1 ! Wd 2 4 tt'lc2! Wd 1 ( 4 . . . 'i!td 3 5 'it>e 1 ! '>t>xc2 6 �e2) 5 tt'lb4! Wd2 6 tt'ld5.

1... 'iit>d2!

2 tt'lf3+ �d3!

Now it is pointless playing 3 tt'le1 + 'it>e3! 4 tt'lc2+ '1t>d2 5 tt'lb4 'it>e3 6 tt'ld5+ 'it>e4 7 tt'lf6+

'ite3. To win , the opponent must be given the move. But how can this be achieved?

3 'iit>e 1 ! 'it>e3 4 tt'le5 'it>e4

In the event of 4 . . . 'iit>d4 White wins by 5 tt'lg4!

'it>d3 6 'it>d 1 , breaking forward with the king, since 6 . . . f3 fails to 7 tt'le5+.

5 tt'lc4! '.t>d3 5 . . .f3 6 tt'ld2+, or 5 . . . 'it>d4 6 'it>e2 ! .

6 tt'ld2 'it>e3 7 tt'lf3 'it>d3 8 'it>f1!

The knight's circular journey has enabled White to achieve his aim - he has given the opponent the move. The rest is already familiar to us.

8 ... 'it>e3

9 tt'le1 'it>d2 10 tt'lc2! 'it>d1 11 tt'lb4! 'it>d2 12 tt'ld5

R. Reti, ^A. Mandler 1 924

Here White's task is even more d ifficult than in the previous study. The winning plan suggested there (which in itself was not at all obvious) does not work here: the left edge of the board interferes. After all, the knight has no square equivalent to the important b4-square in the previous example.

True, a new possibility has appeared - the activation of the king along the route d 1 -e1-f1 -g2-f3. It is obvious that White has no other win ning pla n . Black will try to prevent it by attaching his king to the e2-pawn from d2 or d 1 . It is easy to imagine that here too mutual zugzwang positions cannot be avoided . Let's try to work thi ngs out!

Let's suppose that White's knight is on d3, his king on f1 , and the black king on c2.

More about the 'Montaignian' Knight

ttJ

1 1 1 is one of mutual zugzwang.

The following step i n our logical analysis of the position is to clarify the importance of the e4-square for the knight. Let us suppose that the knight stands on e4, the white king on d 1 , and the black king on b3. Then if it is White to move 1 �c1 ! is decisive. But things are no easier for Black if it is him to move: if 1...Wb2 there follows 2 tt:Jc5! 'it>c3 (2 .. . �b1 3 tt'le6) 3 �e 1 ! , and the afore-mentioned position of mutual zugzwang is reached with Black to move .

Thus the knight must be brought to the e4-square. This is not at all easy to achieve, seeing as White constantly has to watch out for . . . d4-d3. the required position of mutual zugzwang with his opponent to move.

12 . . . 'it>c2( c4) the white king has finally gained the opportu­

nity to break free.

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PART II Technique

Mark Dvoretsky

In document Diseño del electrodo de puesta a tierra para un sistema hvdc (página 75-80)