Saturday, August 5, 2017

The Positional Sacrifice

Many of us are happy to give up material if it means an unstoppable attack. How about sacrificing for the position? That’s where many players hesitate. For some reason it is particularly painful for us to part with a pawn or the exchange for some long-term positional gain.

That’s because by nature, we humans prefer immediate results. By sacrificing something that has been drilled into beginners as one of the most important assets of the game, of course we want something good to justify it. An unstoppable mate or an irresistible king hunt looks tangible enough. But something more abstract, like superior piece activity or a passed pawn, doesn’t look convincing enough to amateurs. So when it comes to sacrificing for the position, the verdict stands: We can’t do it!

Just take the leap, they said

Obviously we have to remove this rigor mortis, if we want to win more games. In his classic work “How to Reassess Your Chess (4th Edition)”, Jeremy Silman takes the bull by the horns by removing material advantage from its holy seat, and placing it alongside other positional factors known as “imbalances”. He explains the way to overcome this mental reluctance to part with material as follows:

“(The player) has to train himself to view each imbalance as something wonderful, and he has to view material as just another imbalance to be collected or rejected, depending on the nature of the individual position.”

 That means that while material advantage is important, you shouldn’t place it on a pedestal and lose sight of all other positional imbalances. Rather, it should be weighed alongside other factors such as the centre, pawn structure and piece activity, and treated equally.

Here is a simple example of how material can be given up for a huge positional advantage, again taken from Silman’s book:

White to move

White enjoys more space, and would love to put a piece on that inviting e6 square. But the only access point, the e-file, is contested by both sides, and Black has no intention of giving it up! So if White tries something like 1. Rxe7 Rxe7 2. Re1 Rxe1 Black trades off the rooks and White can never exploit his spatial advantage.

But now, armed with the knowledge that material is just an imbalance like any other positional factor, you might not take long to find the positional sacrifice:

1. Re6!!

And the reason for giving up the material becomes clear: After 1… Bxe6 2. dxe6, Black’s position is totally hopeless! True, he may be an exchange up, but if we analyze the imbalances of both sides we see a very different picture:

Position after 2. dxe6

  1. Up an exchange

  1. Enormous central space, giving White’s pieces far more activity as compared to Black’s
  2. A strong, protected passed pawn
  3. Weak enemy pawns on d6 and f6 to attack
  4. An outpost on d5 for the knight
  5. Uncontested light-squares along the h1-a8 diagonal that can be used as an invasion route for the light-squared bishop.
  6. Superior minor pieces compared to Black’s rooks: Without any open files, the Black rooks are in fact worse off than any of White’s pieces!

From the assessment of the imbalances it is not difficult to tell that White is winning despite his material deficit. After something like Nd5 and Re1, the weight of White’s forces will crush Black underfoot.

A less extreme example can be seen in the following game, between Petrosian and Spassky in the 1969 World Championship. I must digress for a bit to talk about Tigran Petrosian, who was remembered not only for his impenetrable defensive style, but also his fondness for giving up the exchange to get a superior position. So if there is any role model to look for while studying the idea of the positional sacrifice… look no further than Iron Tigran!

Iron Tigran, the master of positional play

Spassky, Boris vs Petrosian, Tigran V
World Chess Championship 1969 (Round 11)
Position after 30. Nd2

Black has a position similar to our first example: More space on the queenside, and control over the c-file. But Petrosian is unable to use the c-file to invade Spassky’s position, since all the invasion points have been covered by White. 30… Rc7 followed by Rac8 doubling rooks on the file comes to mind, but White can simply reply Rdc1 and Rac1 trading off all the rooks, resulting in a drawish, closed position. Is there a way for Black to push forth his agenda of advancing on the queenside? Turns out there is, and if we remember what White did in our first example, the candidate move here shouldn’t be hard to find:

30… Rc4!

If White accepts the sacrifice with 31. Nxc4 dxc4, we see that Black gets excellent compensation after laying out the imbalances:

  1. Up an exchange

  1. Two strong, protected passed pawns on the queenside
  2. An open diagonal for his light-squared bishop
  3. A backward e3 pawn to attack

This isn’t as clear as the first example where Black was totally cramped up, but the monster passed pawns on the queenside are more than enough to make White think twice about grabbing the material. Spassky wisely declined the sacrifice, instead finding other ways to keep the game complicated:

No article on the positional sacrifice would be complete without Petrosian’s classical defence sacrifice example. The next position is a famous one that some of you might find familiar, but such masterpieces never get too old to be shared:

Position after 25. Rfe1

Things are going badly for Black: White threatens Bf3 followed by d5, setting the central pawn mass in motion and wreaking havoc in Black's camp. If only Black could get his knight to d5 via e7, but moves like … Ra7 or ... Red7 don't work because of the pawn advance e6. This means Petrosian must find a move that can help set up a blockade on both d5 AND e6, which seems impossible unless some concessions can be made...

We have seen two fine works of art by Petrosian, but I cannot resist showing another one. I will cap off this article with another of his masterpieces, where he sacrificed the exchange to set loose a rampaging pawn army, eventually overrunning the enemy with its numbers:

Through these games we can see how material, at the end of the day, is just another positional imbalance. Weighed against other positional elements it definitely carries more advantage, but one must be prepared to let it go when you see an even better opportunity coming your way.

So don’t be afraid to make that positional sacrifice; even if it doesn’t work, at least you have overcome your mental block and learned much from it!

“How to Re-assess your Chess: 4th Edition” by Jeremy Silman

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