In the previous article, we talked about rook versus one pawn, where in the vast majority of cases, it was a question of whether the rook can win or if it is only a draw with a few extreme rare exceptions where the pawn wins.
In this article, we will be adding a pawn to the picture, or looking at rook versus two pawns. This can be more difficult for the rook to fight against, esecially if the kings are far away from the pawns. We will be covering two main topics along with subtopics within:
Connected Pawns
Separated Pawns
Connected Pawns
The scenario where the two pawns are connected is the easier scenario of the two as general principles cover the vast majority of situations. Let's run through them one-by-one, and then finally cover the one difficult scenario.
Principle 1: When the king is in front of the pawns, the side with the rook wins.
Even in the following scneario, where the rook appears poorly placed, it's still a win.
Principle 2: When both kings are far away, two unattacked connected pawns on the sixth rank beats a rook. This holds true no matter where the rook sits provided it cannot immediately take one of the pawns.
Principle 3: When the rook has to do the work of stopping the connected pawns, always get behind the farther advanced pawn.
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Principle 4: When the side with the pawns has the king aiding them, and the opposing king is not in front of the pawns, the result is often dependent on how far away the king is, and every king move matters.
In the following example, which is from an actual game played in 1994 between Thorhallsson and Sadler. We see that the black king is fairly close to the pawns, but it is not in front of the pawns. Delicate play is required to win this one.
Separated Pawns
We have already seen what happens when only one pawn amongst separated pawns is advanced. For those that haven't seen it or don't recall, take a look at the previous article on Rook vs Pawn, the first problem.
Therefore, he we will cover what happens when both the pawns are far advanced. It turns out, how many files apart the pawns are can often make a significant difference.
Let's first start with what was the end of a study that Richard Reti conducted back in 1929.
Now let's look and see what happens when Black has two pawns on the sixth rank separated by one file in between them along with his king in the region, and what happens when Black has two pawns on the sixth rank separated by two or more files in between with his king in the region.
With one file in between the pawns, it's a win for the side with the pawns.
But with two or more files between the pawns, it's only a draw.
Like most endgames, it is always about exact situations, and one square or one rank or one file can make a big difference.
Problems
Problem 1 - Black's king is so far away that he is actually lost. White to move and win.
Problem 2 - The situation of the kings is slightly different than the fourth example. White is still winning. It is Black to move here. Clearly 1...Ke7 2.Rg4 wins for White. But if Black plays 1...g2, how does White win?
Problem 3 - The two black pawns are daunting on the seventh rank. Yet, White has a way to survive. How? White to move and draw.
Solutions
Problem 1 - White wins by relocating the king since he has time given the location of the blank king. 1.Kb6 (1.b6 doesn't work. 1...Ra5+ and the position is equal after 2.Kc4 Rxa6. Note that 1...Rxa6? loses to 2.b7 Ra5+ 3.Kc4 Ra4+ 4.Kc3 Ra3+ 5.Kb2) 1...Kd2 2.Ka7 followed by b6-b7-b8.
Problem 2 - The trick to this problem is seeing that you cannot directly attack the f-pawn after you've taken the g-pawn. After 1...g2 2.Rxg2 Ke6, White must play 3.Rg5!, cutting off the black king. After 3...Kf5 4.Rh5 Kg6 5.Rd5 Kf6 6.Kb7 Ke6 7.Rh5 Kf6 8.Kc6 Kg6 9.Rd5 Kf6 10.Kc5 Ke6 11.Rh5 Kf6 12.Kc4 and now the king is inside the box of the f-pawn. A couple of items to note. First, if Black advances the f-pawn, then once it gets to f2, you play the rook to the back rank followed by Rf1 and Rxf2. The black king cannot get there in time. It should also be noted that the white king needs to remain west of the rook. If it crosses the Rook's path along the 5th rank, the black king can get it. If it crosses the file the rook is on before it gets inside the box of the pawn, then the rook may not be able to get to the back rank if Black advances the pawn.
Problem 3 - White must ignore the pawns and go for the mate threats on the black king. 1.Ra1+ Kb8 2.Rb1+ Kc8 3.Ra1! (Threatening 4.Ra8# if Black promotes either pawn) 3...Kd8 4.Kd6 Ke8 5.Ke6 Kf8 6.Kf6 Kg8 7.Ra8+ Kh7 8.Ra7+ Kh6 9.Ra8 with a similar mate threat as we saw on the third move. The two black pawns eliminate the esacpe if Black tries to run down the h-file. 9...Kh5 10.Kf5 Kh4 11.Kf4 and now 11...Kh3?? 12.Rh8 would be mate. Therefore, Black cannot escape the constant threats of mate and the position is drawn.
Author's Note: Normally, this article is published every other Monday. However, because I will be out of town the week of March 18th, the next article will be published on the morning of Saturday, March 16th, and then resume its normal schedule with the following one coming out on Monday, April 1st.
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