Difference between revisions 26150 and 26843 on enwiki

This is a sample game of [[chess]].


 +---+---+---+---+---+---+---+---+
 | '''r''' | '''n''' | '''b''' | '''q''' | '''k''' | '''b''' | '''n''' | '''r''' | 8
 +---+---+---+---+---+---+---+---+
(contracted; show full) | P | P | P | P |   | P | P | P | 2
 +---+---+---+---+---+---+---+---+
 | R | N | B | Q | K | B |   | R | 1
 +---+---+---+---+---+---+---+---+
   a   b   c   d   e   f   g   h 

Black makes a worthless move.
He needed to defend his pawn with 
2...Nc6 or counter-attack white's pawn with 2...Nf6.
Either knight move would maintain the balance of the game by contesting the center.

The move 2...  f6 appears to defend the threatened e-pawn, but this is an illusion, as the game shall demonstrate.
Black has weakened his king  side, allowing attacks on the f7 square, which is protected by nothing other than the king itself.

3. Nxe5

 +---+---+---+---+---+---+---+---+
 | '''r''' | '''n''' | '''b''' | '''q''' | '''k''' | '''b''' | '''n''' | '''r''' | 8
 +---+---+---+---+---+---+---+---+
 | '''p''' | '''p''' | '''p''' | '''p''' |   |   | '''p''' | '''p''' | 7
 +---+---+---+---+---+---+---+---+
 |   |   |   |   |   | '''p''' |   |   | 6
 +---+---+---+---+---+---+---+---+
 |   |   |   |   | N |   |   |   | 5
 +---+---+---+---+---+---+---+---+
 |   |   |   |   | P |   |   |   | 4
 +---+---+---+---+---+---+---+---+
 |   |   |   |   |   |   |   |   | 3
 +---+---+---+---+---+---+---+---+
 | P | P | P | P |   | P | P | P | 2
 +---+---+---+---+---+---+---+---+
 | R | N | B | Q | K | B |   | R | 1
 +---+---+---+---+---+---+---+---+
   a   b   c   d   e   f   g   h 

White attacks immediately.
This move is somewhat speculative, because white does not yet have enough pieces out to develop a convincing attack.
A purer play would be 3.Bc4, attacking the weakened f7 square and hoping to build a coordinated, irresistable attack.

On the other hand, after the display of weakness in black's second move, white can hardly be faulted for going for the jugular.

3... fe

 +---+---+---+---+---+---+---+---+
 | '''r''' | '''n''' | '''b''' | '''q''' | '''k''' | '''b''' | '''n''' | '''r''' | 8
 +---+---+---+---+---+---+---+---+
 | '''p''' | '''p''' | '''p''' | '''p''' |   |   | '''p''' | '''p''' | 7
 +---+---+---+---+---+---+---+---+
 |   |   |   |   |   |   |   |   | 6
 +---+---+---+---+---+---+---+---+
 |   |   |   |   | '''p''' |   |   |   | 5
 +---+---+---+---+---+---+---+---+
 |   |   |   |   | P |   |   |   | 4
 +---+---+---+---+---+---+---+---+
 |   |   |   |   |   |   |   |   | 3
 +---+---+---+---+---+---+---+---+
 | P | P | P | P |   | P | P | P | 2
 +---+---+---+---+---+---+---+---+
 | R | N | B | Q | K | B |   | R | 1
 +---+---+---+---+---+---+---+---+
   a   b   c   d   e   f   g   h 

Another poor move by black.
The only way to try for an equal game was 3...  Qe7, ''skewering'' the white knight, pawn, and king.
That is to say, the queen would indirectly be attacking everything in the e-file.
After the knight moves away, the queen can take on e4 with check, safely regaining the pawn.

Retaking the knight now merely invites the white queen to jump into the battle.
The fact that black can't afford to take the knight shows that 2...  f6 didn't really protect the pawn at all.

4. Qh5+

 +---+---+---+---+---+---+---+---+
 | '''r''' | '''n''' | '''b''' | '''q''' | '''k''' | '''b''' | '''n''' | '''r''' | 8
 +---+---+---+---+---+---+---+---+
 | '''p''' | '''p''' | '''p''' | '''p''' |   |   | '''p''' | '''p''' | 7
 +---+---+---+---+---+---+---+---+
 |   |   |   |   |   |   |   |   | 6
 +---+---+---+---+---+---+---+---+
 |   |   |   |   | '''p''' |   |   | Q | 5
 +---+---+---+---+---+---+---+---+
 |   |   |   |   | P |   |   |   | 4
 +---+---+---+---+---+---+---+---+
 |   |   |   |   |   |   |   |   | 3
 +---+---+---+---+---+---+---+---+
 | P | P | P | P |   | P | P | P | 2
 +---+---+---+---+---+---+---+---+
 | R | N | B |   | K | B |   | R | 1
 +---+---+---+---+---+---+---+---+
   a   b   c   d   e   f   g   h 

The game's first check!  There are three legal ways to respond to check:
#Capture the piece giving check.  Here this is impossible, as black has nothing which can move to h5.
#Interpose a piece between the king and the piece giving check.  Black could play 4...  g6.  But that would lose a rook to 5.  Qxe5+ and 6.  Qxh8.
#Move the king out of check.  Moving the king to f7 leaves it in check, and its thus illegal, so e7 is the only square for moving out of check.

Note that white has ''forked'' the king on e8 and the pawn on e5.
There is no time for black to protect both, so no matter what he does to get out of check, the white queen can take on e5.

4... Ke7

 +---+---+---+---+---+---+---+---+
(contracted; show full) +---+---+---+---+---+---+---+---+
   a   b   c   d   e   f   g   h 

This is an excellent move to keep the pressure on black.
Because it develops a piece and gives check, white prevents black from consolidating.

If white played less energetically with 6.Nc3, his advantage would evaporate instantly.
Black could answer with 6...
  Be7, giving the king room to retreat to f8.
Once black gets his king to safety, he might actually be winning.
White has only two pawns for the sacrificed knight, which leaves black at a material advantage.

6.... d5

 +---+---+---+---+---+---+---+---+
 | '''r''' | '''n''' | '''b''' | '''q''' |   | '''b''' | '''n''' | '''r''' | 8
 +---+---+---+---+---+---+---+---+
 | '''p''' | '''p''' | '''p''' |   |   | '''k''' | '''p''' | '''p''' | 7
 +---+---+---+---+---+---+---+---+
 |   |   |   |   |   |   |   |   | 6
 +---+---+---+---+---+---+---+---+
 |   |   |   | '''p''' | Q |   |   |   | 5
 +---+---+---+---+---+---+---+---+
 |   |   | B |   | P |   |   |   | 4
 +---+---+---+---+---+---+---+---+
 |   |   |   |   |   |   |   |   | 3
 +---+---+---+---+---+---+---+---+
 | P | P | P | P |   | P | P | P | 2
 +---+---+---+---+---+---+---+---+
 | R | N | B |   | K |   |   | R | 1
 +---+---+---+---+---+---+---+---+
   a   b   c   d   e   f   g   h 

Black makes an excellent defensive move.
Never forget that moving the king isn't the only way to get out of check!

Admittedly, black's d-pawn is a dead duck.
It is attacked by white's bishop, queen, and pawn, three times altogether, while it is defended only once, by black's queen.
The sacrifice is worthwhile, though, to open up lines for the queen and bishop so they can help with the defense.
Now if white fails to find the best continuation, black has some chance to counter-attack.

(contracted; show full) | R | N | B |   | K |   |   | R | 1
 +---+---+---+---+---+---+---+---+
   a   b   c   d   e   f   g   h 

Check again!
White doesn't give black a chance to do anything constructive.
Let's review the three ways to get out of check:
#Capture the piece giving check.  Black could play 7...
  Qxd5.  But white would simply take queen with 8.  Qxd5+.  With such a huge material disadvantage and an exposed king, black could resign without feeling like a quitter.
#Interpose a piece.  Black could play 7...  Be6.  But that would be inadvisable, because the bishop would be defended only once (by black's king) and attacked twice (by white's queen and bishop).  In fact, white could end the game at once with 8.  Qxe6++ checkmate!
#Move the king.  Alas, the only square which is not under attack by white is g6, even further into the open.  It beats the alternatives, though.

7... Kg6

 +---+---+---+---+---+---+---+---+
 | '''r''' | '''n''' | '''b''' | '''q''' |   | '''b''' | '''n''' | '''r''' | 8
 +---+---+---+---+---+---+---+---+
 | '''p''' | '''p''' | '''p''' |   |   |   | '''p''' | '''p''' | 7
 +---+---+---+---+---+---+---+---+
 |   |   |   |   |   |   | '''k''' |   | 6
 +---+---+---+---+---+---+---+---+
 |   |   |   | B | Q |   |   |   | 5
 +---+---+---+---+---+---+---+---+
 |   |   |   |   | P |   |   |   | 4
 +---+---+---+---+---+---+---+---+
 |   |   |   |   |   |   |   |   | 3
 +---+---+---+---+---+---+---+---+
 | P | P | P | P |   | P | P | P | 2
 +---+---+---+---+---+---+---+---+
 | R | N | B |   | K |   |   | R | 1
 +---+---+---+---+---+---+---+---+
   a   b   c   d   e   f   g   h 

Now white must think of a way to continue the attack.
He would like to play 8.  Qf5+, driving the black king to h6 where it can be cornered and checkmated, but black's c8 bishop is guarding the square f5.
If black hadn't interposed with 6...  d5, he would now be subject to a forced checkmate.
As it stands white has to be more creative to keep the initiative.

8. h4

 +---+---+---+---+---+---+---+---+
 | '''r''' | '''n''' | '''b''' | '''q''' |   | '''b''' | '''n''' | '''r''' | 8
 +---+---+---+---+---+---+---+---+
(contracted; show full)
Black's position is still precarious, but there is no immediate way for white to force checkmate.

Now let us take a step deeper into chess reasoning.
White knows black is on the run for the moment, but if he has a chance to regroup, the game is far from over.
Three pawns for the sacrificed knight is roughly material equality.

If white brings additional forces forward with 9.Nc3 or 9.d4, the obvious developing moves, black will harass the white queen with 9...
  Bd6.  That would force white to lose time protecting the queen.  Black would gain time to get his pieces out and get his king to safety.

White desperately wants a quick kill, but can't see how to get it.
He is annoyed that the black bishop on c8 prevents him from playing 9.Qf5+ and administering the coup de grace.
Therefore he asks himself, what if there were no black bishop on c8?
If only that annoyance were removed, I could do great things.

9. Bxb7
(contracted; show full)
Nothing can save black short of white forgetting his plan, but there is some logic to the black move.
Where can the white queen go?
Any black piece she could take is protected.
If white trades queens, then the attack is over, and black is winning.
Finally, if the white queen simply retreats, black will strike back with a check of his own: 13...Qxe4+!


But white must have foreseen this possibility, or he would never have played 12.Qf7 instead of 12.  Bxg5.

13. hg+

 +---+---+---+---+---+---+---+---+
 | '''r''' | '''n''' |   |   |   | '''b''' | '''n''' | '''r''' | 8
 +---+---+---+---+---+---+---+---+
 | '''p''' | '''b''' | '''p''' |   | '''q''' | Q |   |   | 7
(contracted; show full)
Finally, the black queen can't capture the white rook because she is ''pinned''.  If she moved away, the white bishop on c1 would be giving check to the black king.

Notice that, although material considerations are very important in chess thinking, you don't win by having the most pieces.
You win by delivering checkmate!
White was behind in material the entire game, including in the final position, but came away with the victory nonetheless.