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

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