When you get any profits from a sacrifice and are able to calculate how to win the material back this is the case you can sacrifice a pawn. How to see the profits and how to calculate that you can win the material back tells this article.

Let us try to find the answers to these questions based on the example of my game. Playing for White I got a nice position that is in the picture below:

It’s White to move. What does White want? White has the numerical advantage of the pawns in the queen side and in the center. It’s good idea to pass these pawns forward in the both parts of the board (see the red arrows). Thus, White disperses the Black forces among these board sides creating tension either in the queen side or in the center.  Dispersed forces of Black lose the interaction and either let White to pass a pawn to the point of promotion or lose the material.

What prevents White from carrying out this plan? This is the knight that blocked the path of the d pawn and controls the b5 square on the path of the b pawn. The “e4” move suggests itself to knock the knight off from its square. However, White sacrifices the d pawn in this case as Black may respond by moving N c7. After that, the White’s bishop is attacked as well as the d pawn is attacked too. Thus, White loses the pawn taking its bishop out of the attack.

So, we found the profit from the sacrifice – the possibility to pass the pawns with all the ensuing consequences (see above). Now we have to calculate if we can win the material back if Black accepts the sacrifice. If Black accepts the sacrifice it gets the isolated pawn in the d4 square. This pawn is defended by the bishop only. So, our idea is to put White’s king near this pawn and attack it with the knight also. Thus, White’s knight takes this pawn and White wins the material back.

Let us count tempos required to implement our plan. The variation where Black accepts the sacrifice is the following: 25. e4 N c7 26. B c4 ed. Thus, we get the position in the picture below:

This picture shows that White needs the five tempos to implement its plan (see the red arrows) assuming that Black moves along the green arrows in the picture. The “a4” move is needed to prevent the “a5” move of Black. Thus, In this variation, White has enough tempos to win the pawn back. Let us record this variation: 27. a4 g5 28. K f1 h5 29. K e2 K f8 30. K d3 K e7 31. N e2 h4 32.  N x d4.

Now we have to look for the changes of this variation that may prevent to implement this plan. This might be 31. … Be4 instead 31. … h4. Thus, Black threatens to take the h2 pawn. In this case, the game may continue:  31. N e2 Be4 32.  g3 g4 33. N x d4 and White wins the pawn back again.

What else Black may invent to prevent White’s plan? Black may transfer its knight along the e8 -> f6 way to attack the White’s e4 pawn. This variation might be like that: 27. a4 g5 28. K f1 N e8 29. Ke2 Nf6 30. f3 N d7 31. b4 B e5 32. Bb5! N f8 33. G3 N g6 34. K d3 h5 35. N e2 B c7 36 N x d4 and White wins the pawn back again:

Again, we have to look for the changes of this variation that may prevent to implement this plan. This might be 35. … B d6 instead 35. … B c7. Thus, Black threatens to take the b4 pawn. In this case, White plays 36. a5. And after, 36. … B x b4 White plays 37. a6 and the White’s pawn is unstoppable.

What else Black may invent to prevent the White’s plan? Black may try to change the sequence of the knight’s moves and the bishop’s moves comparing with the previous variation. Say, Black plays 29. … B e5 instead of 29. … N f6. In this case, the game may continue: 30. g3 N f6 31. f3 N d7 32. B b5 N c5 33. b4 N e6 34. K d3 h5 35. K c4 B d6 36. a5 ba 37. ba B c7 38. a6 B b6 39. K d5 h4 40. gh gh 41. N d3 B a7 42. K c6 h3 43. K b7 B c5 44. a7 B x a7 45. K x a7 and Black loses too much material to save the game. Thus, White wins thanks to the king’s journey across the whole board.

Thus, we studied how to calculate variation. Firstly, a chess player invents the start variation that is not bad for a competitor and makes it sure that the plan works in this variation. Then the player looks for the changes of this variation that may prevent the player’s plan and finds the ideas to repel the threats found. Then the player thinks about that how the competitor may modify his or her game to prevent the player’s plan. After this, the player modifies the plan to make it working in the new variation and so on.