The most fundamental of the chess endings are those that occur when there are only kings and pawns left on the board. The importance of studying these openings cannot be stressed enough as they are the foundation of all endgame theory. At any time in the early endgame or late middlegame, all of the pieces could exchange, leaving only kings and pawns, so you have to always know whether the king and pawn ending that would result from your current position trading down is favorable or not. The four most important things about king and pawn endings are material, king position, passed pawns, and weaknesses, and in this article we’re going to look specifically at weaknesses in these endgames.
On an empty chess board, put a white king on f3, white pawn on d4, black king on f6, and a black pawn on d5, and assume it’s white’s turn to move. While this position is symmetrical, there is a somewhat hidden factor. White can force the black d5-pawn to be weak because he can gain the opposition and force the black king away from it’s defense. Take a look at 1. Kf4 Ke6, 2. Kg5 Kd6, 3. Kf6 Kd7, 4. Ke5 Ke7, 5. Kxd5 Kd7. Now, even though white has won the pawn, the game is a draw because black has now gained the opposition. The result of the game is not important, however. What you should take from this example is that from a completely symmetrical position, white was able to win a pawn in what seemed like a very innocent position. If there was a white pawn on c3 and a black pawn on c4 in the starting position, the play would follow exactly the same, except white would be clearly winning.
Here is a position with a similar idea: put a white king on c4, white pawns on e5, f4 and g5, a black king on c6, and black pawns on c5, f5, and g6 with white to move. Both sides have a passed pawn, but it looks like black has white blocked from getting access to his kingside pawns. You’ll notice that as the base of a pawn chain, black’s g6-pawn is weak, similar to the previous position. White breaks through with 1. e6 Kd6, 2. e7 Kxe7, 3. Kxc5 Ke6, 4. Kc6 and we already see what’s happening. White will force the black king to the corner and eventually win the black g6-pawn. Play continues 4. … Kf7, 5. Kd7 Kg8, 6. Ke8 Kg7, 7. Ke7 Kh8, 8. Kf8 Kh7, 9. Kf7 Kh8, 10. Kxg6 and white wins easily. The forcing continuation after 1. e6 only works because white has a weakness to hone in on. In this position, the weakness was the g6 pawn.
These two positions perfectly illustrate the key concepts needed to take advantage of weak pawn chain bases. An advanced king position with correct manuevering can always win the pawn chain base if played correctly, but like in the first example, if there aren’t multiple pawns on the board, then sometimes winning this pawn isn’t enough. Mastery of this concept will greatly advance your understanding of pawn weaknesses in general, not just in the endgame, so it’s very important. Study hard, and good luck in your games.