Rook and King
This is trickier and takes a little longer, but the checkmate is always there if you know what you are doing. The checkmate will look something like this:
Once again, the checkmated king is on the edge of the board. The rook takes away the h-file, while the White king takes away the g-file.
The rook takes away the afile, while the White king covers the b-file.
The rook covers the first rank while the White king takes away second-rank squares.
Opposition
You've already encountered opposition in the last chapter. There you used it to help shepherd a pawn to the promotion square or to prevent a pawn from getting to the promotion square.
There are many books devoted to checkmate on the market. The simplest are those of A. J. Gillam, who fills up his books with checkmate positions or positions one move from checkmate. Others include Bobby Fischer Teaches Chess, which is a step-by-step explanation of how to find the lurking checkmating patterns in positions two and three moves away from the final checkmate.
The way to use it in king and rook versus rook positions is to take an entire rank or file away from the opposing king using the opposition. Thus, your king fulfills the role of one of the rooks in the two-rook checkmate.
The idea of gradually taking squares away from the weak king is the whole key to this checkmate plan. The weapons you use are the opposition and the tremendous long-range power of the rook, which can take away an entire file or rank from the lone weak king, or lose a move in order to persuade that monarch to step into the opposition himself. When your prey is finally in jail, with nowhere left to go, it is time for the checkmate.
Taking Squares Away
Here's how to do it. This is really nothing more than a slower way to execute the two-rook checkmate. It's just that your king isn't as powerful as the other rook was. So you have to use the opposition to take a rank or file away from the weak king.
Kings already in opposition. 1. Rf6+ Kc7 2. Kc5 Kd7.
Kings not yet in opposition. 3. Kd5 Ke7 4. Rf1.
This last move is the key. White does not move into the opposition. Rather, he gently persuades Black to move into the opposition himself by dropping back with his rook.
The Black king is about to step into the opposition again. 4…. Kd7 5. Rf7+ Ke8 6. Ke6 Kd8.
Keep the king confined. 7. Kd6 Ke8.
Checkmate! 9. Rf8 checkmate.
Not yet opposition again. 8. Rf2 Kd8.
The Back Rank Mate
The back rank mate, also referred to as the corridor mate, is one that can be executed only by a major piece. It is the mate that ends the king and major piece against king positions. It can take place on a side file as well as a side rank. But it can also come about when the next file or rank is denied the checkmated king by something other than an enemy king and opposition. Following are some examples.
White checkmates with 1. Rd7.
White checkmates with 1. Qc6.
White checkmates with 1. Rf7.
White checkmates with 1. Rg6.
