Saturday, March 29, 2014

A difference wth an extra pawn: Part 1

I guess most of you have figured out the solution by now, so I won't waste time. Once again here are the 3 positions:

Position 1

Position 2

Position 3

For the first two positions, the game is a dead draw even though Black is two pawns up. But for Position 3, Black can win easily.

Sounds a little crazy? Then let's take a step back and imagine all 3 positions without the extra pawn on the 4th rank. You should know by now that will mean a draw, so long as White shuffles his rook along the h-file, and keeps the king on a2 and b2.

Note those words in italics; that's the reason why White can draw our first two positions. As long as the extra pawn is on the a or b file, it cannot help to chase away the White king from either a2 or b2, and White maintains the draw by the old rook shuffle.

So for example in position 1, White draws after 1... a3 2. Ka2! (NOT 2. Kxa3?? Ra1+ 3. Kb2 h1=Q losing) and White sticks his king on a2 forever, while his rook dances along the h-file and kicks away the Black king with a check should he get too close to his h2 pawn.

...

How about position 3? Black wins because his c-pawn can pull the White king off the critical a2 and b2 squares:

2... c3+
3. Kc2

There is no way the king can stop both pawns at once. After 3. Kxc3 White loses to 3... Rc1+ 4. Kd2 h1=Q, while after 3. Ka2 c2 the c pawn will march to promotion.

3... Ra1
4. Rh5+

White's best try; after 4.Rxh2, 4... Ra2+ wins the White rook with a skewer.

4... Kd4
5. Rh4+ Ke3
6. Rh3+ Kf4

Now if White continues to keep up the checks Black simply marches his king to the h-file to destroy White's checking distance.

7. Rxc3 h1=Q
0-1



One thing that's so beautiful about chess is how a small shift, no matter how imperceptible, can make a world of difference!

...

Before we end off Part 1, I will leave y'all with another rook endgame position:

White to play and win

Of course you know that if that Black pawn on c5 were to suddenly vaporize, then White will have a similar winning position that we saw in Position 3. So his main goal will be to try to get rid of that pawn... but how?

Accurate play is needed here, so you can challenge yourselves again to try to solve this problem. We'll go through it in Part 2; have fun! (:

Links:
The Vancura Position: http://nushsblackknights.blogspot.sg/2014/01/the-vancura-position.html
Passive rook + Pawn on 7th rank (Part 1): http://nushsblackknights.blogspot.com/2014/02/2nd-lunar-new-year-challenge.html
Passive rook + Pawn on 6th rank: http://nushsblackknights.blogspot.sg/2014/02/passive-rooks-shall-stay-passive.html

Sources:
"Silman's Complete Endgame Course" by Jeremy Silman

Wednesday, March 26, 2014

Challenge yourselves: A difference with an extra pawn?

As we resume on our journey in rook endgames, let us start out simple before we go on to the more complex topics. So how many of you remember the following position?

Dead draw

We already now that this position is a dead draw as long as White keeps his king on a2 and b2, and shuffles his rook along the h-file.

(Yes, since many of us are probably too accustomed to seeing White as the stronger side, I decided to make a change for now)

So now, take a look at the following 3 positions (all Black to move):





And of course the question is: For each of these positions, can Black win, or will it be a draw?

By now this should be quite trivial for many of us, so cracking this puzzle won't take long. Have fun! (:

Monday, March 24, 2014

Rook Endgames: The journey so far

Before we continue on, let us consolidate what we've learned so far in our rook endgame journey. If you've missed out any of the content that we've covered, the links are all below for your convenience:

Basics

The building blocks that form an integral part of our rook endgame education, and we are all expected to know the ins and outs of these basics by now.

Lucena and Philidor Positions: http://nushsblackknights.blogspot.sg/2013/12/revising-basic-rook-endgames-part-1.html

File denial and Tarrasch's Rule: http://nushsblackknights.blogspot.sg/2013/12/revising-basic-rook-endgames-part-2.html

Active vs Passive rooks: http://nushsblackknights.blogspot.sg/2013/12/revising-basic-rook-endgames-part-3.html


Intermediate

"Lucena" with a rook pawn: http://nushsblackknights.blogspot.sg/2013/12/a-lucena-with-rook-pawn.html

Connected passed pawns: http://nushsblackknights.blogspot.sg/2014/01/rook-vs-rook-connected-passed-pawns.html

The Vancura Position Part 1: http://nushsblackknights.blogspot.sg/2014/01/the-vancura-position.html

The Vancura Position Part 2: http://nushsblackknights.blogspot.sg/2014/02/passive-rooks-shall-stay-passive.html

Pawn on the 5th rank: http://nushsblackknights.blogspot.sg/2014/02/rook-5th-rank-pawn-vs-rook.html

Pawn on the 4th rank Part 1: http://nushsblackknights.blogspot.sg/2014/03/rook-vs-4th-rank-pawn-rook-part-1.html

Pawn on the 4th rank Part 2: http://nushsblackknights.blogspot.sg/2014/03/rook-4th-rank-pawn-vs-rook-part-2.html

Pawn on the 4th rank Part 3: http://nushsblackknights.blogspot.sg/2014/03/rook-4th-rank-pawn-vs-rook-part-3.html

...

So perhaps you may think that by now, immersing yourself in this ocean of information must have left you with a considerable amount of rook endgame knowledge. And the good news is: Yes, if you've managed to master all that has been presented above, then your rook endgame skills will be enough for you to outplay many others at the tournament level, and you will no longer feel as helpless when entering the endgame.

The bad news is: Our knowledge of rook endgames is still very much in its infancy. Seriously, the realm of rook endgames is just so vast and boundless that the content above doesn't even cover 50% of it. So that means that we still have a long way to go before we can achieve dominance in heavy artillery. Hold on tight, my brothers!

Friday, March 14, 2014

Rook + 4th rank pawn vs Rook: Part 3

We will wrap up our discussion of this topic today. By now our experience with rook endgames is enough to tell us that positions with rook pawns always prove to be exceptions to endgame norms; but in this case, even knight pawns have become an exception!

What do I mean!? Well there's only way to find out why: Tackle the problem head-on!


Knight pawns

Draw... but why?

(See the KnightVision viewer below for better visualization)

1. Re2

1. Kh4/Kf4 will be met by a rook check from the 8th rank, and after retreating back behind the pawn White won't make any progress. So he can only pass time and hope for Black to mess things up.

Now here's the interesting bit. How should Black play now?

To make things simple I'll present four choices over here: Only one of them draws, while the other three lose for Black.

1... Rg7
1... Ra8
1... Kd4 
1... Kd6
.
.
.
.
.
.
.
.
.
.
Let's look through them one by one.

1... Rg7? destroys the Black rook's checking distance, so not surprisingly it loses after 2. Kh4 Rh7+ 3. Kg5 Rg7+ 4. Kh5 Rh7+ 5. Kg6

1... Ra8? is clearly not the way to go because after 2. g5 we have a winning position with the pawn on the 5th rank, and the Black king cut off by 2 files on the long side of the board (Have fun browsing back if you're unfamiliar: http://nushsblackknights.blogspot.sg/2014/02/rook-5th-rank-pawn-vs-rook.html)

After 1... Kd4? things start to get interesting, but Black loses after 2. Re6 Kd5 3. Rh6!

Black loses!

And suddenly White has cut off the entire 6th file and beyond to the Black king! Now White can simply walk his king up to h5, and slowly advance his pawn past the 5th rank. So for example the game can continue: 2... Ke5 4. Kh4 Kf4 5. Rf6+ Ke5 6. g5 Rh8+ 7. Kg4 and Black loses because his king is cut off by one file along the long side of the board.

...

So that leaves us with one last option:

1... Kd6!

Surprising, but it works! Let's see how:

2. Re4

Of course 2. Kh4 is met by 2... Rh8+, while 2. Rd2+ (or any other move that takes the White rook off the e-file) allows the Black king to get closer to the pawn with 2... Ke5

2... Kd5

And now we see the point of 1... Kd6: Black can now shuffle between d5 and d6 (preventing White from winning by the Re6-Rh6 maneuver) and White cannot advance the pawn because it is being shadowed by Black's rook.

Of course, 2... Kd7? loses after 3. Kh4 Rh8+ 4. Kg5 Rg8+ 5. Kf6 Rf8+ 6. Kg7 1-0

3. Re1 Kd6
1/2-1/2

White cannot make any progress as long as Black keeps his king on d5 and d6.



...

That seemed easy, but by now perhaps some of you might be wondering why this Kd5-Kd6 maneuver does not work if the pawn were a central/bishop pawn? We will look back now and see why; at the same time this will also help us understand why knight pawns are exceptions to the general rules for this position.

Perhaps before we progress you might want to do a little revising: http://www.nushsblackknights.blogspot.sg/2014/03/rook-4th-rank-pawn-vs-rook-part-2.html

How did White win again...?



Suppose we gave Black the move now:

1... Kc6

But this time White won't need to resort to Re4; he has something more effective:

2. Kg4! Rg8+
3. Kh5 Rf8

3... Rh8+ 4. Kg6 will slowly destroy the Black rook's checking distance

4. Rf1

And now we see why knight pawns are exceptions: Had the pawn been on g4 rather than f4, White would not have been able to use the Kh5-Rf1 trick because the short side of the board is too narrow for him to do that! In this position, White now wins because Black's king is too far away to reach the pawn in time

4... Kd5
5. Kg6
1-0

And the pawn will slowly advance to f7 under king and rook protection, while the Black rook will eventually be forced out of its passive position.


Rook pawns

As usual rook pawns are always exceptions which tend to be a bother for the stronger side:

Dead draw

And the draw is simply too easy for us to see here: White's king has no file on the right to step onto, and if he tries to step out from the other side with 1. Kg4 then Black just trades rooks with 1... Rg8+ 2. Kf2 Rxg1 3. Kxg1 reaching a drawn rook-pawn position. So Black can simply shuffle his rook between h8 and h7, and if 1. Rf1+ then alternating his king along the f and g files should seal the draw.

Once again as a personal challenge you can try finding out how many files the Black king has to be cut off by before White can secure a win. Of course you might want to refer to the following link: http://nushsblackknights.blogspot.sg/2013/12/a-lucena-with-rook-pawn.html


Wrapping up

Alright, we're going to pause our study on rook endgames for now, so as to let y'all prepare for our upcoming National Individuals. Brush up on your tactics, familiarize yourself with a couple of opening repertoires and learn some important positional concepts. As for rook endgames, do try to consolidate what we've learned so far. It is important that you know at least the basics before facing the enemy next week.

We will resume our journey after NSI is over. All the best, guys!

Links:
Pawn on the 5th rank: http://nushsblackknights.blogspot.sg/2014/02/rook-5th-rank-pawn-vs-rook.html
Pawn on the 4th rank Part 1: http://nushsblackknights.blogspot.sg/2014/03/rook-vs-4th-rank-pawn-rook-part-1.html
Pawn on the 4th rank Part 2: http://nushsblackknights.blogspot.sg/2014/03/rook-4th-rank-pawn-vs-rook-part-2.html

Sources:
"Silman's Complete Endgame Course" by Jeremy Silman

Friday, March 7, 2014

Rook + 4th rank pawn vs Rook: Part 2

Let us continue where we left off previously. In a Rook + 4th rank pawn vs Rook position, we have seen how the weaker side has drawing chances if his king is only one file away from the pawn. Today, we will see how the stronger side can force a win if his opponent's king is cut off by 2 files or more from the pawn.

Yes; regardless of whether the weaker king is on the long or short side of the board, the end result is still the same!


The long side of the board

White wins regardless of who to move

White can exploit the short side of the board to foil any of Black's checking plans, so the win should be easy for many of us.



1. e5

White can also try 1. Kf4 Rf8+ 2. Kg5 Re8 3. Re1! (Tarrasch's Rule) Kc6 4. Kf6; because the Black king had been cut off by two files, he arrives at the pawn too late and White protects it in time. Now the Black rook has insufficient checking distance from both the 8th rank and h-file, and its passive position can only stop the inevitable advance of the White pawn for so long.

1... Ra4

An idea we have seen previously; sadly it won't work here because Black's king is too far away to stop the pawn.

2. e6

Fortunately for White, Black's king blocks the b-file and prevents 2... Ra6; note that had the Black king's original position been on b5 rather than b6, then White must learn to look out:


Be careful over here!

1. e5 Ra4 and now don't throw away the win with 2. e6?? Ra6! Fortunately, White keeps it good and simple with 2. Kf3 Rh4 3. e6 Rh6 4. Re1 returning to a similar winning position in our main line analysis.

Returning to our main line:

3... Ra3+

Or 2... Rh4 3. Kf3 where Black's checking distance along the short side of the board has been crippled. So the game can continue along the lines of let's say 3... Rh6 4. Re1 Rh8 5. e7 Re8 6. Kf4 Kc6 7. Kf5 Kd6 8. Kf6 where Black's passive rook once again leads to his doom. Notice that because the Black king was cut off by two files, White's king could reach the pawn in time to protect it!

3. Kd4 Ra2
4. Ke5 Re2+

5. Kf6 Rf2+
6. Ke7
1-0

Our old friend is returning!

By now you should be experienced enough to recognize an old friend at our doorstep: The Lucena Position.


The short side of the board

This is slightly tricker, but now because the weaker side's king is cut off by two files instead of one, the stronger king has a place to hide from the enemy rook checks:

White still wins



1. e5 Ra3+

1... Ra4 takes us back to an idea we discussed earlier: 2. Kd3 (And not 2. e6?? Ra6 with a draw) 2... Kh7 (2... Ra8 3. Kd4 Re8 takes us to a winning 5th rank pawn position, which you should be familiar with by now) 3. e6 Ra6 (If Black tries to keep up the checks with 3... Ra3+ White eventually finds a hiding place with 4. Ke4 Ra4+ 5. Ke5 Ra5+ 6. Kf6 followed by an upcoming Lucena Position) 4. Re1 Ra8 5. e7 Re8 6. Kd4 Kg7 7. Kd5 Kf7 8. Kd6 (D)

Black is hopelessly bogged down

With yet another passive rook position; there is no stopping 9. Kd7 followed by promotion. Notice that because the Black king was cut off by two files, he was too far away to reach the pawn in time!

Returning to our main line:

2. Ke4 Ra2

Or 2... Ra4+ 3. Kf5 and White's king has sought shelter, leading to a winning 5th rank pawn position we have discussed in an earlier topic.

3. e6 Re2+
4. Kf5 Rf2+
5. Ke5 Re2+
6. Kf6 Rf2+
7. Ke7
1-0

A shelter on e7

White's king is tucked away behind the pawn, and we have yet another upcoming Lucena Position!

...

That was pretty easy. So here's a couple of useful tips on winning this position when the enemy's king is cut two or more files away:

  • Use your rook to keep the enemy king cut off until you can put your rook safely behind the pawn, after which both your king and pawn will be able to win the race hands down.
  • Use the pawn to shelter your king from any rook checks from the long side of the board
  • Be careful not to push the pawn too recklessly; watch out for drawing traps!

Let us stop here for now; in Part 3, we will look at how the position can be different when we have knight or rook pawns!

Links:
Pawn on the 5th rank: http://nushsblackknights.blogspot.sg/2014/02/rook-5th-rank-pawn-vs-rook.html
Pawn on the 4th rank Part 1: http://nushsblackknights.blogspot.sg/2014/03/rook-vs-4th-rank-pawn-rook-part-1.html

Source:
"Silman's Complete Endgame Course" by Jeremy Silman

Saturday, March 1, 2014

Rook vs 4th rank pawn + Rook: Part 1

I guess I've given y'all enough time to look through our previous challenge. Now let's look at the position again:

White to move: Can he win?

And most of ye got it correct: White can't win here, because the pawn is too far back and Black's king is close enough to keep it in check.

As a general rule of thumb, the stronger side wins if the weaker king is cut off by two files or more from the pawn. If the weaker side's king is closer, it is often easier to force a draw; however, this is also determined by the position of his king, and whether he is on the Long or Short side of the board (I hope you remember what these terms mean; otherwise go back to our previous topic!). If he can safely step in front of the pawn or gain the opposition after trading rooks, he can easily save his half-point.

While these guidelines holds true for central and bishop pawns, knight and rook pawns are exceptions; we will talk about that in a follow-up article. For now let's focus on central pawns.

As a reminder, this article will utilize most of the terms and knowledge that we have gained in the previous topic (5th rank pawn + rook endgames), so do make sure you are familiar with the content covered earlier on before we proceed: http://nushsblackknights.blogspot.sg/2014/02/rook-5th-rank-pawn-vs-rook.html


Central pawn, 1 file away, king on 6th rank

We return to our first position:

Draw regardless of who to move

The position here is a draw because of the following:

  • White's pawn is on the 4th rank, which gives Black's rook sufficient checking distance from the last rank (remember that when the pawn was on the 5th rank, White's king was too close to the last rank for Black to check safely from there. Always keep in mind that your rook must be as far away from the enemy king as possible when checking!)
  • The Black king's ideal position on c6 allows him to try some tricks which help to tie down White's pieces into defending each other. The variations here are quite tricky, so we shall go through in detail.



1. Kf4

Stepping out to support the advance of the pawn. If 1. Rc1+ Kd6 Black's king gets in front of the pawn

A trickier try is 1. e5 but Black can simply cut off the king with 1... Ra4 (1... Re8?? 2. Ke4 and White has a winning 5th rank pawn position, where Black's king is cut off by a file on the long side of the board) 2. e6 (2. Rd6+ Kc7 and Black's king gets in front of the pawn)

Now White threatens to win with e7 followed by Rd8, but Black stops this with a timely 2... Kc7! 3. e7 Ra8 with a draw. Note that if the king were on c5 rather than c6, this 2... Kc7 maneuver will not work; we will explore that later.

1... Rf8+

Notice how in our previous topic, the last-rank defense failed because the Black rook had insufficient checking distance. But here, it works because the rook is too far away to be stopped.

Also note that if Black tries 1... Rh8 threatening 2... Rh4+, it will fail because his rook is on the short side of the board with insufficient checking distance. Fortunately for him, he does not have to resort to this!

2. Kg5

Or 2. Ke5 Re8+ 3. Kf5 Rf8+ 4. Ke6 Re8+ with no victory in sight.

2... Re8

And not 2... Rg8+?? where White can get close to Black's rook with 3. Kf6 Rf8+ 4. Ke7 1-0

3. Kf5 Rf8+
4. Kg6 Re8
5. Rd4 (D)

Things are getting tricky

White tries something new, since 5. Kf5 Rf8+ gives no progress. This is the part where things get tricky for Black, so hold on tight!

5... Kc5!

Now both White's rook and pawn are attacked so he cannot advance the pawn. Notice that if the Black king were on c7 rather than c6, things might turn out differently; we will look at this later.

But Black's troubles aren't over yet: White still retains many threats to evade the rook checks and advance the pawn, so caution is required.

6. Rd5+

Of course 6. Rd1 Rxe4 will be foolish for White.

6... Kc6
7. Kf5 Rf8+
8. Ke5

The other variation is 8. Kg4, where Black draws by luring the White rook off the d-file so as to let his king step in front of the pawn. However, careful play is important as it is easy to botch up the position: 8... Re8 9. Kf4 Rf8+ 10. Rf5 Ra8. White's last move sheltered his king from the checks, but leaft the d-file open for Black's king to pass through. Now Black will not want to play 10... Rxf5+?? because after 11. exf5 he loses the opposition and the game. Rather, he gets his rook out of the way first. before marching his king in front of the pawn.

11. Rf7 (11. e5 Kd7 and Black is on his way to creating a Philidor Position) 11... Kd6 (D)

Position after 11... Kd6

12. Kf5 Ra5+ 13. Kf6 Re5 14. Rd7+ Kxd7 15. Kxe5 Ke7 and Black draws since he has the opposition.

Returning to our main line, things get easier after 8. Ke5:

8... Re8+
9. Kd4 Re7!

You'll see the point of this weird looking move later on!

10. e5

Or 10. Rc5+ Kd6 stepping in front of the pawn.

10... Rd7!

So that was the purpose of 9... Re7; by relocating to the 7th rank, Black can force a trade of rooks that allows his king to step in front of the enemy pawn!

11. Rxd7 Kxd7
12. Kd5 Ke7

1/2-1/2

With a hopelessly drawn king + pawn vs king position.


Central pawn, 1 file away, king on 5th rank

Remember how I said earlier that Black might run into some problems if his king were on c5 rather than c6? Let's take a look!

White to move wins since Black is on the long side of the board

In such a position, the outcome is determined by whether the weaker side's king is on the Long or Short side of the board.

If it were Black to move he will simply draw by 1... Kd6 returning to our first position. But if it were White to move, he wins because Black's king is stuck on the long side of the board.



1. e5 Ra4

Attempting to cut off the king as usual, but now White can exploit the Black king's unfortunate position:

2. Rd8! Rh4
3. Kf3

Exploiting the Short side of the board: Black cannot shuffle his rook safely, and if he goes over to the long side the Black king gets into the way!

3... Kc6

Notice how if the king were initially on c6 rather than c5 he could simply play a timely 3... Kc7 kicking the White rook away. But now the pawn has time to rush over and protect his fellow rook:

4. e6 Kc7

Black would love to play 4... Re4 and put his rook behind the enemy pawn, but the presence of the White king on the fatally short side of the board prevents him from doing so. Meanwhile, 4... Rh6 is answered with 5. e7

5. e7
1-0

There is no stopping the pawn from promoting.

So how does Black draw if his king were cut off on the short side of the board instead? In the interest of time I won't go through this; you can try it as a personal challenge (:


Central pawn, 1 file away, king on 7th rank

Similarly, if the Black king was initially on c7 instead of c6, Black's situation becomes problematic because he does not have a Kc5 defensive idea to counter Rd4.

White to move wins, Black to move draws

If it were Black to move he can draw in two different ways: 1... Kc6 (returning to our first position) or a faster method by 1... Rd8 (what's the best way to get rid of a sniper? Well, snipe him back!)

Mother of God...

2. Rxd8 Kxd8 3. Kf4 Ke8 (NOT 3... Ke7?? 4. Ke5 losing the opposition) and Black draws after taking the opposition.

If it were White to move, however, then he wins with the Rd4 trick because Black can no longer use the Kc5 defense:



But what happens if the Black king were on the short side of the board? Can he still draw? Once again, I will leave this to you as a personal challenge!

...

Ok, I admit that even I myself got quite confused when typing this. It seems there are so many factors to take into consideration when the pawn is on the 4th rank. So let us try to tidy up what we've learned in this article to make things easier.

For a rook + pawn vs rook position where the pawn is  a central/bishop pawn on the 4th rank, and the weaker side's king is cut off by one file, the following general rules will help determine the outcome of the game:

  • If the weaker side's king is separated from the pawn by one rank (i.e. on the 6th rank), then he can force a draw regardless of whether he is on the long or short side of the board!
  • If the weaker side's king is on the 5th, 7th or 8th rank, however, then the side of the board (and who to move) determines the outcome of the game. As a rule of thumb, the weaker side should strive to place his king on the short side of the board, so that his rook has sufficient checking distance on the long side.
  • As usual, the game often steers towards a draw if the weaker side can get his king in front of the pawn.

In Part 2, we will look at how the stronger side can force a win if the weaker side's king is cut off by two files or more from the pawn.

Links:
Pawn on the 5th rank: http://nushsblackknights.blogspot.sg/2014/02/rook-5th-rank-pawn-vs-rook.html

Source:
http://imgur.com/gallery/BNw77
"Silman's Complete Endgame Course" by Jeremy Silman