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2. MEMORIA DESCRIPTIVA

2.9. R ED DE ABASTECIMIENTO DE AGUA POTABLE

2.9.2. Diseño

2.9.2.1. Red de abastecimiento de agua fría

An isolated pawn, a doubled pawn, or a backward pawn is usually thought to be weak. Indeed, most amateurs will do just about anything to avoid these kinds of pawns because they believe the pervasive misinformation that labels such pawns as doomed to eventual destruction. This kind of labeling is actually a form of chess bigotry. Why should the words

iso­

lated, doubled,

or

backward

signify that a pawn is

weak?

In chess, a pawn or a square is only weak if it can be attacked. If an enemy piece cannot get your

pawn, then there is no reason to worry about its safety, regardless of whether it is isolated, doubled, or backward.

DIAGRAM 84.

White to play Petrosian-Barcza

Budapest, 1955

In Diagram 84, we see a position where the so-called weak pawns ac­

tually deserve their name! Black's pawns are all horribly weak. They are so rotten, in fact, that White will just eat one after another. The Black pawn on b6 is isolated and stands on an open file, which makes it easy to attack. The Black d- and h-pawns are also isolated, and the miserable dou­

bled f-pawns speak for themselves. Compare this wreck of a pawn posi­

tion to White's pawns. All the White pawns, with the exception of the

The Creation of Targets

The first victim falls. N�w 2.Nxf6+ is threatened.

1 .

.

. Rc6 2.Rxc6 Rxc6 3.Ra8+ Kd7 4.Ra7+ Rc7 5.Rxc7+

White, who is dining on Black pawns and will soon have a significant material advantage, is happy to trade pieces because this thinning of mate­

rial keeps Black's counterplay to a minimum.

S

..•

Kxc7 6.Qxh7 Qa2+ 7.Kf3 Qd2

Black threatens 8 ... Qd l

+.

8.Qbl !

White stops the check. When you are ahead in material, your first pri­

ority is to stop all enemy counterplay (see Chapter Three). Then if you can restore the positional balance, your material edge will give you a certain victory.

8

••.

f5 9.Ng3

All the White pieces come home to aid their King.

9

•.•

Bh4 1 0.Ne2

White gives Black nothing with this move. Playing either 10.QxfS Qdl + or 1 0.Nxf5 Qf2+ would make things unnecessarily messy.

l0

••.

Be7 l l.h3 Bb4 12.Ng3

Now the possibility of a check on

f2

is gone, so White can eat again.

12

.•.

Kc6 13.NxfS KbS 14.Nd6+ Ka4 15.Nxf7 Ba3 1 6.NeS

Having devoured everything, the satiated Knight returns home. Be­

cause 1 6 ... Bcl can now be met by either 1 7.Ng4 or 1 7.Qd3, Black gives up. He has endured more than enough punishment!

Now let's compare the doubled pawns in the game we just looked at with the ones in the next example. The position in Diagram 85 came about after these boring but common opening moves:

l.e4 eS 2.Nf3 Nc6 3.Nc3

Nf6 4.Bc4 Bes S.0-0 0-0 6.d3 d6. In

this position (typically seen in

chil-dren's matches), White can play the excellent

7.BeJ!,

after which 7 ... Bxe3 8.fxe3 gives White doubled e-pawns.

DIAGRAM 85. White to play

Why does White allow this? The doubled pawns are welcomed by White because he sees that, at the moment, the pawn on f2 is doing noth­

ing at all. On e3, though, it becomes a dynamic contributor because the doubled pawns on e3 and e4 defend the critical d4, d5, f4, and f5 central squares.

In

addition, the f2-pawn's absence from the f-file gives White a half-open file for his Rooks. Finally, White also sees that his doubled pawns will not be weak. Do they appear weak to you? The e4-pawn is well defended, so the only pawn that could by any stretch of the imagina­

tion be a target is the guy on e3. How can Black attack this pawn? It doesn't stand on an open file, so the enemy Rooks can't do anything to it.

After something like 8 ... Ng4, White can simply defend himself with 9.Qe2 (or 9.Qel ) and then chase the bothersome horse away with h3 . So these doubled e-pawns are not weak at all. On the contrary, they are active par­

ticipants in the battle for key central squares.

Given all these considerations, Black would be well advised to avoid 7 ... Bxe3 and instead play either

7 ... Bb6

(inviting 8.Bxb6? axb6!, which suddenly gives Black an a8-Rook with a half-open file to use and doubled h-pawns that are not weak at all) or

7

...

Bg4!.

After the latter move, 8.Bxc5

The Creation of Targets

dxcS would make Black happier than White. Why? Because the c-pawns are quite safe (let White try to attack them after Black plays ... b7-b6!), and the pawn on cS helps control the important d4-square. To make matters even better for Black, the pawn' s removal from d6 gives Black use of the half-open d-file, which benefits both his Queen and Rooks.

Clearly, doubled pawns are no� necessarily weak! Attackable weak pawns might result from an enemy error, but you cannot count on any op­

ponent to make this kind of error. It is up to you to find ways to create these weaknesses. That is what this particular strategy is all about. Once you create the target, then you can go all out and attack it. One of the most useful methods of creating weak pawn targets is a strategy known as the

minority attack,

which goes like this:

Employ two pawns to attack a pawn majority of three, with the