Now you might be wondering what is meant by "Simple". We all know that chess is not simple. Well, when it comes to rook and pawn vs rook, one could write an entire book on it. John Nunn actually wrote a book that was over 350 pages long on just rook and a single pawn versus rook. He covers every scenario of the pawn on the a-file, b-file, c-file, and d-file, and every square from the second to the seventh ranks. The e-file, f-file, g-file, and h-file are symmetrical to the d-file, c-file, b-file, and a-file, respectively. Some of these endings are fairly simple, and some of them are difficult enough to give a master problems.
Therefore, since we are in the early phases of this column, we will be talking about the "simple" cases that are essential to know no matter what level player you are. In general, when talking about "simple" cases, other than a few scenarios in the case of the rook pawn, the side with the pawn will usually have his king near the pawn. This will occur in this column and the next one. Here, we will be talking about the most basic scenarios where the player with the pawn wins. In the next column, we will discuss the most basic of drawing techniques for the side without the pawn.
What makes the knowledge of these "simple" scenarios of rook and pawn versus rook endings so important is that often times, when a few more pieces or pawns are on the board, knowing whether to trade down or not is often dependent on you knowing whether the resulting position is won or drawn for the side with the pawn. Therefore, when you get to the problems in this article and the next, you may see additional material on the board, and you will need to determine whether or not to trade down into the rook and pawn versus rook ending or not.
So in this section on the "simple" cases where the pawn wins, we will break it down into two parts:
A) Non-Rook Pawns
B) Rook Pawns
A) Non-Rook Pawns
If you only get one thing out of this article, make sure it is this one! In this section, we will be looking at scenarios where the player with the pawn doesn't have a rook pawn, and has a winning position.
To do that, we will be talking about a method of execution called "Lucena's Position". What on earth is Lucena's Position?
Lucena's Position involves a number of steps.
Step 1 - Cut off the opposing king - The first and most important thing for this to work is that the opposing king must be cut off from the file the pawn is on. So, for example, if you have an e-pawn, the king must be kept away from the squares in front of the pawn on the e-file.
Step 2 - Advance the pawn to the seventh rank with the assistance of the king - Using the king as a guide, if the pawn isn't already there, the pawn needs to be brought to the seventh rank
Step 3 - Push the opposing king at least three files away from the pawn - This will usually involve checking the king with the rook at a time that it cannot come closer to the pawn, whether it be that it cannot do it legally, or for tactical reasons, which we will cover.
Step 4 - Build the bridge - A bridge must be built to cut off the opposing from capturing the pawn at the time of promotion.
So let's look at a few specific examples. The first example is the textbook scenario that illustrates the winning method. The commentary in the following diagram is critical and should be read multiple times until fully understood.
So now that we have looked at the textbook example, let's look at some slightly more advanced scenarios, some of the exceptions and why certain methods don't work, such as other defense attempts by the side without the pawn.
The first thing I want to do is illustrate why this method doesn't work with a rook pawn.
The following position will illustrate why it doesn't work for the defending side to try to wrap the king around the back of the pawn.
This final example we will see of Lucena's Position will be one where the pawn isn't yet on the seventh rank (or technically the second rank in this case as it will be Black that has the pawn in this example), and the note to White's 8th move will illustrate the importance of doing the four steps given above in the proper order.
B) Rook Pawns
As we saw in the second example above, Lucena's Position does not work with rook pawns as the king then has nowhere to go to get out of the way of the pawn.
Instead, with a rook pawn on the seventh and the king in front of it, a different method involving the rook going to the promotion rank is necessary, and as we will see in the examples below, this requires the king to be driven not three files away like in Lucena's Position, but instead five files away! We will look at two positions. One where the king is cut off five files away, and one where he is only cut off by four files to show why five files are necessary.
First, let's look at the winning method when the king is five or more files away.
As you can see, it is a lot more difficult to win with a rook pawn. Now let's look and see why White cannot win if the white rook and black king are both a file closer to the pawn.
So as you can see, just a rook each and one pawn can make things very complicated, and this is just the tip of the iceberg when it comes to rook endings. Now let's test your knowledge with three problems.
Problems
Problem 1 - There are multiple ways for White to win this position, but using the method of Lucena's Position covered in this article, how does White win this?
Problem 2 - In the final example of Lucena's Position given above, you saw the end of my third round of the 2015 North Carolina Open. Well, the following position comes from the fourth round of that very same tournament, played the very next morning. I was White in this position. At first glance, it appears as though White is simply going to lose the a-pawn. What did I do to set up yet another instance of Lucena's Position and win this game?
Problem 3 - We saw this position earlier where White plays 3.Rb8 and wins. However, in this instance, it is Black to move. Can Black draw the position with it being his move or not?
Solutions
Problem 1 - White wins by following the four steps in order. 1.Rf1 - Step 1, cutting off the black king. 1...Rg2 2.g7 - Step 2, advance the pawn to the seventh rank. 2...Rh2 3.Re1+ - Step 3, push the black king three files away from the pawn. 3...Kd7 4.Re4 - Step 4, build the bridge. Now the zig-zag method works. 4...Rh1 5.Kf7 Rf1+ 6.Kg6 Rg1+ 7.Kf6 Rf1+ 8.Kg5 Rg1+ 9.Rg4 and White wins.
Problem 2 - White wins by giving away the a-pawn, realizing he can win the e-pawn, and create an instance of Lucena's Position. 1.Re7 Rxa6 2.Kf6 Ra4 3.Ke5 Kc8 4.Rxe6 Kd7 5.f5 Ra1 6.Kf6 Rf1 7.Re2 and now we have Lucena's Position. White won after 7...Kd8 8.Kg6 Rg1+ 9.Kf7 Rf1 10.Rd2+ Kc7 11.f6 Kc8 12.Kg7 Rg1+ 13.Kf8 Rf1 14.f7 Kc7 15.Rd4 and Black resigned as the bridge is built and White will use the same zig-zag method to bring the king to f5 that he used to get the king to f8 and advance the pawn in the process.
Problem 3 - With Black to move, he can draw. Two moves must be avoided. 1...Kd7?? and 1...Rb2?? both lead to the winning positions for White analyzed before after 2.Rb8. The solution for Black is to get the rook off the b-file at once. A move like 1...Ra1 or 1...Rh1 draws for Black. If 2.Rb8, then 2...Kc7! leads to the drawn position analyzed in the final diagram before the problems. If 2.Kb7, then 2...Rb1+ and it's a draw because the white king has no escape. The c8-square is blocked by his own rook and the c5-square is covered by the black king, blocking the other escape, and 3.Ka6 Ra1+ 4.Kb6 Rb1+ 5.Ka5 Ra1+ is simply a draw. What this problem shows is that whoever is to move in any given position can often times make a major difference in the endgame.