The Chess Coach
by SunilWeeramantry

There are several criteria that are applied when evaluating a
position, the two most common being material and mobility. 
Together they can confer a tangible advantage. But all the king's
horses and all the king's men will not be able to avert defeat if the
king himself is vulnerable to a mating attack.  

Many players, even experienced ones, are lulled into a false sense
of security when their king is neatly tucked away behind a few
pawns.  But pawns on ceremonial duty are not effective defenders. 
The illusion of safety is easily shattered by a few well-placed
enemy pieces that have clear lines of attack to the king.  It takes
only a few hard losses to appreciate the fact that king safety is
more a function of the enemy's ability to attack than the extent of
the pawn cover around one's own king.

A powerful way of eliminating the protection around the king is to
employ a combination that is referred to as a destructive sacrifice. 
One such attacking pattern is the double bishop sacrifice which
was first introduced into grandmaster play by Emmanuel Lasker in
1889.  This sequence features the annihilation of the castled
position by sacrificing both bishops to expose the opposing king.
Once the king is out in the open, the remaining attackers, generally
the queen and a rook, will join forces to deliver checkmate. Here is
an example from a game between two of the most prominent
players of their time.

Nimzowitsch-Tarrasch, St. Petersburg 1914
White: Kg1, Qc2, Rc1, Rf1, Bb2, Nd2; pawns - a2, b3, d4, f2, g2,
h2.
Black: Kg8, Qe7, Rd8, Rf8, Bc6, Bd6; pawns - a7, c5, f7, g6, h7.

Observe how Black's bishops are training their sights on White's
castled position.  The time is ripe for a combination.  1...Bxh2+ 
2.Kxh2 Qh4+  3.Kg1 Bxg2!  4.f3.  Naturally, White cannot accept
the second sacrifice with 4.Kxh2 because 4...Qg4+  5.Kh1 Rd5 
6.Qxc5 Rh5+  7.Qxh5 Qxh5+  8.Kg2 Qg4+ wins the knight and the
game.   4...Rfe8  5.Ne4 Qh1+  6. Kf2 Bxf1  7.d5 f5  8.Qc3 Qg2+ 
9.Ke3 Rxe4+!  10.fxe4 f4+  11.Kxf4 Rf8+  12.Ke5 Qh2+  13.Ke6
Re8+  14.Kd7 Bb5 mate.  I t is not unusual to see a king who has
been driven out of his home take a desperate run across the board
in a futile bid to escape. 

Even if the attack does not conform to an established pattern like
the double bishop sacrifice, a superiority of attacking forces in the
vicinity of the opposing king, coupled with a lack of defensive
mobility, is generally sufficient to win.  The game Keres-Szabo,
from a match between the Soviet Union and Hungary in 1955,
illustrates the point.  This game is analyzed in some detail in "Paul
Keres: The Quest for Perfection" by Keres and John Nunn,
(Batsford 1997).

White: Kc1, Qe3, Rd1, Rg3, Nc3, Bf1; pawns - a2, b2, c2, e5, g2,
h4.
Black: Kg8, Qa5, Rb8, Re8, Nd7, Bc8; pawns - a6, c6, e6, f7, g7,
h7.

Although each player controls a half-open file to the enemy king
and has good attacking chances, White is in a more secure
defensive position as he has several pieces around his king.  Black,
on the other hand, has only one effective defender, the knight on
d7.  Keres proceeds to eliminate this knight with an inspired
exchange sacrifice, realizing that Black's castled position cannot
withstand the onslaught of the white forces without this piece. 
18.Rxd7 Nxd7  19.Bd3.  Black is helpless as none of his pieces can
come over to help his king.  Nor does a counterattack on the b2
pawn achieve much as the white king is hardly inconvenienced by
the check on b2.  The game ended in short order with a destructive
sacrifice leading the way.  19...h6  20.Qf4 Kf8  21.Rxg7 Kxg7 
22.Qf6+ Kf8  23.Bg6 and Black resigned.  

As we have just seen in the Keres game, destructive sacrifices
work very well when there is a lack of defensive resources. But
they can also work even when a king has some defensive help. 
Consider this position from Gunsberg-Chigorin, St. Petersburg
1890.

White: Kg2, Qe2, Rc1, Rh1, Bb2, Bb1; pawns - a3, b3, d3, e4, f3,
g4.
Black: Kg8, Qh6, Rf4, Rh7, Bh4, Nc6; pawns - a6, b5, c5, e6, e5,
g6
Position after White's 35th move.

Black scored a brilliant victory by breaking into the white fortress
with 35...Rxf3!  White was forced to answer 36.Qxf3 as
recapturing with the king would have failed to 36...Qf4+  37.Kg2
Qg3+  38.Kf1 Rf7+ winning with ease.  And now, 36...Qd2+ 
37.Kg1 Bf2+  38.Kf1 Nd4  39.Bxd4 Qxc1+  40.Ke2 Rxh1 
41.Bxf2 Qxb1 42.g5 Qf1+  43.Resigns.  The fact that the white
queen was close by did not make a difference.  Black was able to
play around her and deny her the opportunity to be an active part of
the defense.
 
There are times, however, when a destructive sacrifice may not
lead to a forced win because a judicious return of material blunts
the force of the attack. Such situations can still establish an
advantage, but only if the attacker accepts the fact that the game
may well need to enter a new phase.  Psychologically, this is not an
easy transition for most of us.

An opening that boldly advertises its aggressive intentions from the
outset is the dangerous Milner-Barry Gambit in the Advance
French.  The question whether White has sufficient compensation
for the sacrificed pawn is still a subject of debate.  The opening
sequence has been thoroughly analyzed and the following moves
are recommended by current chess theory: 1.e4 e5  2.d4 d5  3.e5 c5 
4.c3 Nc6  5.Nf3 Qb6  6.Bd3 cxd4  7.cxd4 Bd7  8.0-0 Nxd4 
9.Nxd4 Qxd4  10.Nc3 Qxe5.   One significant deviation is found at
this point.  Black refrains from snatching the second pawn and
contents himself 10...Ne7 to proceed with normal development. 
11.Re1 Qb8  12.Nxd5 Bd6  13.Qg4 Kf8  14.Bd2 h5  15.Qh3.  For
those readers who may wish to learn more about this opening, I
would recommend a standard reference work such as ECO 'C' as
well as a reliable repertory  book such as John Watson's excellent
"Play the French". 

I walked this well trodden theoretical path at the 1993 New York
State Championship against the formidable Joel Benjamin.  While
I have enjoyed success against several grandmasters over the years,
my record against Joel is abysmal.  Given the many merciless
positional squeezes that I have had to endure at his hands, I was
quite happy this time to find myself in the murky waters of the
Milner-Barry gambit.  Interestingly, Joel did not choose the main
line recommended by Watson and others, namely 15...Bc6, but
elected to play 15...Ne7 instead.  After the moves 16.Nxe7 Bxe7 
17.Rad1 Ba4  18.b3 Bc6  19.Bc4, Black attempted to dislodge
White's light-square bishop with 19...b5.  The point behind the
mysterious 17...Ba4 is now revealed in that Black had wanted to
provoke b3 to deny White's light-square bishop a retreat square
along the b3-f7 diagonal.  But this bishop has other plans.

Weeramantry-Joel Benjamin, New York 1993
20.Bxe6!  This destructive sacrifice is definitely in keeping with
the spirit of the Milner-Barry gambit.  20...fxe6  21.Rxe6.  With his
pawn cover shattered, and his major pieces relegated to the role of
spectators, the black king is in a precarious position.  The
immediate point is that 21...Bd7 fails against 22.Qf3+, when the
reply 22...Ke8 is crushed by a second destructive sacrifice,
23.Rxe7+.  The elimination of Black's dark-square bishop is a
recurring theme.  Without it, Black's task in defending the dark
squares is quite impossible.

21...Qb7.  This activates the queen and attempts to free the queen's
rook.  22.Rc1!  Switching this rook over to the c-file sets up a
direct attack that is difficult to handle.  What can Black do about
his bishop on c6?  Moving back in defense with 22...Be8 is refuted
by 23.Rxe7 Kxe7  24.Qf5, creating a mating net and threatening a
devastating bishop check on one of the diagonals leading to the
black king; pinning the white rook on e6 fails to 23.Qf5+ with the
thematic rook sacrifice to follow; and protecting the bishop with
22...Rc8 leaves the black queen overloaded after 23.Rxe7.  Joel
spent 40 minutes on this next move and decided to return the
material, willing to accept an inferior endgame with 22...Bxg2.

Now after the logical 23.Qxg2 Qxg2+  24.Kxg2, Black must
connect his rooks with 24...Ke7, permitting White to gain the
advantage after 25.Re5.  But I had too many rook sacrifices
swimming around in my head!  With misguided romanticism and a
stubborn refusal to accept the transition into an endgame, I
proceeded with 23.Qf5+ and self-destructed shortly after it became
clear that my attack had floundered.  I was quite disappointed to
say the least, but this game did leave me with a healthy respect for
the obvious discipline of the grandmaster.  I wish all of you many
happy attacks!  But please attack wisely.