What to Trade in Endgames
I would like to address the question of exchanges in endgames. Unlike middlegames, having a material advantage in endgames almost always leads to winning positions. There are different methods of converting either positional or material advantages in the endgame. A chess player should know all of the methods and use the one, which a specific position asks for. Usually what happens is one of the sides does some operation to get into a theoretical position. It is extremely important to know by heart some of the basic theoretical positions of endgames. I will not address here this topic but any endgame book will provide those basic positions that one just has to memorize. Below are a couple of examples of how trading pieces led to increasing one side’s advantage.
Trading pawns when down in material
There is a rule: the side with material advantage should trade pieces, while the side with material disadvantage should trade pawns.
In the following example white has a decisive material advantage: he has an extra passed c-pawn. White also has more space and his king is more active. Black’s main active piece is a rook on d5. According to the above rule it would favor white to exchange this rook. Rd4 of course is an option. There is another way: to take away the knight from c5 and put white’s rook there. Vidmar misplaces his knight, which allows black to trade pawns.
What pieces to leave on the board to convert a minimal advantage?
White has a small advantage: his pieces put considerable pressure on black’s queenside. It looks as if after the natural minor pieces exchange on c6 the game would go into an equal rook ending. White finds a very unusual solution to the problem.
Transformation of advantage
Black’s position is better: the knight on f3 paralyzes white’s kingside. It seems that there is no point in exchanging such a great piece for white’s useless Bg5. White managed successfully to cover all his pawn weaknesses: h4, f2 and a4; there is no way black can break through. Black transforms one sort of advantage into the other: from having a strong knight to having a passed pawn.
Exchange in order to get to a theoretically drawn position
Sometimes exchanges are used in the purpose of defense: to get into a theoretically drawn position or to play a position with drawish tendencies. It reminds me of a famous saying that “all rook endings are drawn.” It is well known that opposite color bishops endings are often drawn even down a couple of pawns, this is so because the defending side can construct a blockade on the color of the squares his bishop is.
In the following example black is down two pawns but if he manages to trade queens things might not be so bad. With the last move he offered a queen swap, let's see how white parried the threat.
Giving up material to go into a theoretically winning position
When one side has more material it is sometimes the shortest way to go to give back some of the material to reach a position maybe with equal material but theoretically winning. In the following example white had a chance to go into a winning pawn endgame by sacrificing his extra bishop.
The article is just an outline of trading in endgames and how it effects the position. One has to be very careful not to fall into some theoretically unfavorable position, like in the fourth example white had to avoid opposite color bishops. There are many more cases like this when one side has two extra pawns but cannot win because it is simply not enough for the given endgame. What pieces to trade in endgames is a very complex topic, since one has to think which material balance will give him the most advantage.
