Category Archives: Ashvin Chauhan

The Passed Pawn – Underpromotion

Last week, we looked at the passed pawn in general. Promoting a passed pawn usually ends the game in favour of the promoter as it creates huge material imbalance if the pawn becomes a queen. But this is not always the case!

Sometimes underpromotion is necessary in order to checkmate the opponent king and to meet opponent’s resources such as counter promotion, checkmate threats, the threat of capturing the promoted piece and drawing tricks. Here are some enlightening examples:

1) Robert Fontaine against Maxime Vachier Lagrave in 2007:

Underpromotion to meet perpetual checks and checkmating the opponent king

Q: How would you proceed with Black pieces?
A: Black can checkmate the opponent king with series of forcing moves using underpromotion.

1… f1=N+!!

This is the only way to pocket the point, promoting the pawn into a queen leads only to a draw after Qxc7.

2.Kf4 Rh4+ 3.Kg5 Be3+!

Sacrificing the rook.

4.Kxh4 g5+
5.Kh5 Ng3+

White resigned in view of 6. Kg6 g4#.

2) Aron G Reshko against Oleg Kaminsky in 1972:
Underpromotion to avoid stalemate tricks

Q: What would you promote to on a8?
A: Promoting to a queen or rook fails to Qf7+!! due to stalemate tricks. In the game White promoted the pawn into a bishop and went on win after couple of moves.

3) Nakamura against Kramnik in 2012:
Underpromotion leaves Black without any counter chances.

Q: How would you proceed with the White pieces?
A: In the game White played 1.c8=N+, the only move to win the game because promoting pawn into queen can be met by exd1=Q+ whilst 1.Kxe2 can be met by f3+ followed by Bxc7. Black tried hard for next 18 moves but failed to save the day. Here are rest of the moves in case you’re interested.

62…Kf6 63.Kxe2 Ke5 64.Nb6 Kd4 65.Bg2 Be1 66.Nd5 Ke5 67.Nb4 Bh4 68.Nd3+ Kf5 69.Kxd2 Kg4 70.Ke2 Bf6 71.N1f2+ Kg3 72.Bf3 Bd8 73.Ne4+ Kh4 74.Ne5 Bc7 75.Ng6+ Kh3 76.Ne7 Bd8 77.Nf5 Bb6 78.Kf1 Kh2 79.Bg4 f3 80.Nh4 1–0

Ashvin Chauhan

The Passed Pawn

This article is aimed at beginners and pre-intermediate players only. Though, intermediate players may find it interesting.

The pawn, the smallest chess unit, increases its value if it advances to the other side of the board with proper support. This is because of its unique power to promote itself to any other piece except the king.

A pawn is a ‘passed pawn’ or ‘passer’ if it doesn’t having any obstruction from an enemy pawn on the same file or neighboring file. Various endgame and middle game themes are based around the passed pawn only. We will deal with those concepts later on.

Let’s consider the following position:

1) White’s ‘c’ and Black’s ‘c’ pawns are not passed pawns as they have frontal obstruction.
2) White’s ‘g’ and Black’s ‘h’ pawns are not passed pawns as they face obstruction from the neighboring file’s enemy pawns.
3) White’s ‘e’ and Black’s ‘a’ pawns are passed pawns.

The level of difficulty in producing and promoting a passer varies with the level playing strength. Sometimes it is easier whilst at other times it is harder and requires the use of various tactical motifs and combinations to achieve the objective. Here are some instructive examples:

Carl Schlechter against Julius Perlis in 1911

In the given position Black’s last move was 7…Bxb1.
Q: How would you evaluate Black’s last move? And how should White proceed here?
A: Black’s last move was a mistake. Now White can win a good pawn.

8. dxc6!!



Black is completely oblivious. He should have played 8…Nxc6 when White is pawn up yet far from winning. But now White can launch a splendid combination which wins on the spot.

9. Rxa7!!

This forces Black to give up his due to White’s powerful candidate on c6 and Black’s awkward knight on b8. But his next move forces him to resign after White’s reply.

9…Rxa7 10. c7

Black resigned as he can’t stop White’s pawn from being promoted.

Karjakin against Navara in 2009

In this position White already had passed pawns on the a- and b- files but they are not dangerous yet because of Black’s active rooks on the 7th rank.

Q: How can White win this position by force?

A: Karjakin played R5c2 which wins by force.

36. R5c2!!

White sacrificed his whole rook in order to make use of his pawn on b6.

36…Rdxc2 37. Rxc2 Rxc2

37…Rxa5 fails to b7 followed by Nd7+.

38. b7 Rb2 39. Nd7+ Ke8 40. Nb6

The point behind the combination. Black resigned.

Ashvin Chauhan

Pawn Levers

Pawns are natural blockaders of lines so every pawn move opens up some lines while closing Others. The quality of your long-range pieces depends upon the availability of open lines. Besides this pawn levers can be very useful in busting the opponent’s pawn structure or improving one’s own pawn structure. Therefore every pawn move and lever must be taken into account very seriously, even if it looks impossible to play them.

Here is an instructive example:

Spasskay against Avtonomov in 1949
White to play and win.

Black’s last move was 11…Nb4. His idea was to create a strong blockade on d5, and at first sight it looks as if no harm can befall him. But Black is in fact already lost here. Find the winning continuation for White!

11. d5!!

A pawn lever looks impossible at first sight. What is the point behind this sacrifice?

11…Nbxd5 12. Bg5!

This is the point and the only winning continuation. Not only does this allow the opening up of lines against the king, but it also breaks up Black’s pawn structure by force.

12…Be7 13. Bxf6! gxf6


13…Bxf6 loses a piece because of pin along the e file whilst 13…Nxf6 loses the queen.

14. Nd4! Kf8??

A blunder under pressure. 14…Qd7 can prolong the fight but can’t change the result. Castling was not possible due to Nc6.

15. Nf5

Threatening Rxd5.


16. Rxd5! Qxd5

Accepting defeat.

17. Qxe7+ Kg8 18. Qxf6

Winning the queen by force. So Black resigned.

Ashvin Chauhan

Recognise the Pattern # 35

Today, we will see a typical exchange sacrifice on c3 (usually taking a knight) in the Sicilian defence. Black players like to make this sacrifice in order to get one or more following advantages:

1) Usually Black ends up with a knight and a central pawn against a rook with White’s busted pawn structure creating additional targets. Even if White has castled short this can prove to be sufficient compensation, though it varies from case to case.

2) White’s king won’t feel safe any longer in the absence of key defender and damaged pawn structure (usually if White castles long).

3) This typical sacrifice also increases the quality of other pieces, particularly Black’s dark square bishop and an active knight in the center.

4) It is very difficult for White to use his exchange in the absence of open files.

Here is an instructive example:

Nakamura against Gelfand in 2013

Q: In a given position Nakamura played 24. f5. How would you with the Black pieces?


24…Rxc3!! 25. bxc3 Qxa3+

25…Ne5 26. Kd2 Bd7 is an option given in chess informant.

26. Kd2 Nf6!

Compare the activity of each side’s pieces. The Black ones are far more active and dangerous than White’s.

27. Qd3

The bishop can’t be taken because of Ne4

27…Bc4 28. Qd4 d5! 29. exd5

29.e5 is bad in view of Ne4+.

29…Bxd5 and White resigned after black’s 41st move. Here is the rest of game in case you’re interested.

30.Rg1 Be4 31.Bd3 Qa5 32.Qb4 Qc7 33.Bxe4 a5 34.Qxb7 Qf4+ 35.Ke2 Rc7 36.Qb6 Nxe4 37.Qd4+ Kh7 38.c4 Rd7 39.Qe3 Ng3+ 40.Qxg3 Qxg3 41.Rxd7 Qe5+ 0-1

Would you like to dig out further on the same theme? Study the following games.

Shirov against Anand in 2008

Mamedyarov against Gelfand in 2011

Movsesian against Kasparov in 2000

Ashvin Chauhan

Revisiting The Patterns

In chess, a player is more successful if they are able to use their knowledge optimally rather than a person who might know more. It has more to do with recognizing patterns on board rather than knowing tonnes of them. That doesn’t mean I am against learning more patterns, it’s more a case of applying what you do know when a pattern arises.

How can someone become good at recognizing patterns?

Here is an answer.

Besides that I would like to add a few points:

I fear not the man who has practiced 10,000 kicks once, but I fear the man who has practiced one kick 10,000 times.
Bruce Lee

You should practice a pattern a lot in its basic form. It is more beneficial to do one or two move combinations on a daily basis rather than doing complicated ones. This was suggested by Dan Heisman in his Novice Nook column at, and although it was for improving tactical skills I believe it can be applied at other areas too.

Give yourself some breaks on regular basis to digest acquired information/knowledge before moving on to the next one. It is also useful for keeping you interested in chess.

Try to organise acquired information in blocks. You can find some examples on the same theme in Capablanca’s Chess Fundamentals and also Silman’s Complete Endgame Course. Another good try can be seen in Chess Tactics From Scratch by Martin Weteschnik. Perhaps organising acquired information in blocks is the essence of recognizing patterns.

Ashvin Chauhan

Recognise the Pattern # 34

Today we will see another typical way to destroy a king’s shelter, this time by sacrificing material on g7/g2. This sacrifice often opens the h1-a8 (a1-h8) diagonal and the g-file and the success of such an attack usually depends upon available whether these can be used. You may need to check the possibilities of further sacrifices to drag out the opponent’s monarch into the danger zone which is very typical with this theme.

Ralf Lau (2460) against Sergey Smagin (2520) in 1990

Q: White’s last move was Nf3-e5. How would you evaluate this move?

Solution: White’s last move was a big mistake as it allows Black to gain a very valuable tempo on the knight by playing d7-d6, which opens up the light square bishop and prepares the typical sacrifice.

19…d6! 20. Nd3 Nxg2!!

Nxc6 leads to the same continuation as the game.

21. Kxg2??
This leads to mate in 5 although 21.f3/f4 doesn’t change the outcome because after Nxe1, black is pawn and exchange up in addition to this Safety of white’s Monarch has been already compromised.


The only way to win.

22. Kxh3 Qf3
23. g5
and White resigned here.

Work for readers!!

Here are some instructive games on the same theme to study:

Bogoljubov against Mieses
Spielmann against Tartakower

Ashvin Chauhan

Recognise the Pattern # 33

Today we will see a typical sacrifice on f6 (f3) in order to destroy a king’s pawn cover. Earlier we discussed the classical Bishop sacrifice and Lasker’s double Bishop sacrifice which had the same goal.

Before sacrificing piece on f6 (f3) one should carefully evaluate the possibility of participation of his major pieces along the g- or h- file (rook lifts are a very typical theme here) and possible ways of declining the sacrifice.

Here is an instructive example:

Tal against Dmitry in 1970

In the given battle White has already lifted his rook and knight and is ready to jump on f6, while on the other side Black’s queen is already cut off from the main battle field although she is attacking the White rook. Therefore White’s queen has to leave the first rank with tempo, which is quite possible after opening up the h-file. In general White’s position has great potential.

Here Tal played:

18. Nf6+!! gxf6 forced
There is no way to decline the sacrifice. If Black plays 18…Kh8 then Nxh7 is simply enough to win.

19. Bxh7+!!

As discussed the White queen needs to leave the first rank with a gain of tempo.


Black is preventing White’s queen being activated with check. If Black plays Kxh7 then Qh5+ followed by Rg1! wins

20. Rh4 Kg7 21. Qc1

Threatening Qh6 mate.

21…Ng8 22. Bxg8

Black resigned here in view of following lines:
a) If 22…Kxg8 then 23.Rb3.
b) If 22…Rxg8 then 23.Qh6.

Otherwise there is no defence to Qh6 except by surrendering the queen on b1.

Work for readers!!
It is recommended that you study the following games on the same theme:
Nunn against Craig William in 1986
Petrosian against Larsen in 1960
Spielmann against Hans Gebhardt

Ashvin Chauhan

Recognise The Pattern # 32

After castling short we tend to play the king’s rook to another open/half open file, abandoning protection of the f-pawn in front of it. Therefore it is quite useful to set your radar for the f7 (f2) square in order to seize any opportunity to launch an attack on castled king. Usually, we sacrifice the piece on that square in order to bring opponent’s monarch from his comfort zone.

Here are a few instructive examples of this theme:

Petrosian against Balashov in 1974

Q: Is it possible to play Bxf7 here?
Hint: This sacrifice will work only if you’re able to find a very calm follow-up on the next move.


22. Bxf7! Kxf7

Ideally Balashov should resign here because sacrifice was made by Petrosian!!
22…Ne5 won’t work because of 23.Qxe5+ Qxe5 24.Nxe5 Bxg5 25.Bxe8 when Black is the exchange and a pawn down.

23. Bh6!!

Now g7 square has been taken away from Black’s king and there is no way to neutralise an attack from e6 or the a2-g8 diagonal (a very important lesson to remember) without losing decisive material.


If 23…Nd4 then 24.Qxd4 Bf8 25.Rxe8 Rxe8 and now Ng5 is just winning. But it was better than the text move.

24. Qc4+ and White went on win after couple of moves.

Blackburne against Collins in 1897

Q: In a given position Black’s last move was 19…Rd8 which is a grave mistake how would you punish it?


It was to better to play 19…Bxe5 followed by Nb6 and it’s still a game but text move leads to immediate loss with

20.Nxf7 Kxf7??

Though other moves can’t change the outcome but this leads to mate in six. Help yourself please.

It is highly recommended to study below classics to enhance your knowledge of this theme:

Colle against Grunfeld
Gurgenidze against Tal

Ashvin Chauhan

Sealing the Weakness

Today I am going to talk about the sealing a weakness by physically blocking lines. It is really a nice theme which beginners often fail to see; when your opponent tries to exchange the blockading piece often you get a passed pawn, a better pawn chain or a nice outpost for a piece.

Here are a couple of examples of this:

Seirawan against Yussupov in 2000

Q: Black has a weakness on c6 but which is not accessible to White in the near future. Could you formulate a plan for Black using the theme discussed above?

Hint: You can seal that weakness by placing a piece on c4. This kind of idea often arises in the QGD Exchange pawn structure.

Solution: Black can bring his knight to c4 via f8-d7-b6 and c4 which not only seals the weakness on c6 but gets a nice outpost.

Here is the rest of game:

20…Nf8 21.Nb3 Qa3 22.Qc1 Nd7 23.Rc2 Qa8 24.Ne1 Nb6 25.Nd3 Nc4 26.Re2 Qc8 27.Nbc5 Rce7 28.Rfe1 Qf5 29.Kg2 h5 30.f3 Qf6 31.a4 bxa4 32.Nxa4 h4 33.Nac5 Qg6 34.e4 hxg3 35.h3 Bxc5 36.Nxc5 dxe4 37.Rxe4 Rxe4 38.Nxe4 Nd6 39.Qxc6 f5 40.Nxd6 Rxe1 41.Qc8+ Kh7 42.Qxf5 Re2+ 43.Kg1 Re1+ 44.Kg2 Re2+ 45.Kg1 Qxf5 46.Nxf5 Rf2 47.Nxg3 Rxf3 48.Kg2 Rd3 49.Ne2 Kg8 50.h4 Kf7 51.h5 Kf6 52.h6 gxh6 53.Nf4 Rxd4 54.Kg3 Kf5 55.Ne2 Ra4 56.Ng1 h5 57.Kh3 Kg5 58.Nf3+ Kf4 59.Ne1 Ra2 60.Nd3+ Kg5 61.Ne5 Ra3+ 62.Kh2 Kf5 63.Nf7 Rd3 0-1

The next example is one of my favourites and a really instructive one:
Janowski against Capablanca in 1916

Q: What will you do with your damaged pawn structure on the queenside? Try to formulate the plan.

Hint: Capablanca uses weak pawn to support the c4 square.

Solution: Black first supports the b5 square by playing 10…Bd7! and then slowly gets the pawn push to b5 in order to bring his knight to c4 via a5-c4 route. The whole game is really instructive and has already been annotated by Nigel D here.

Ashvin Chauhan

Recognise The Pattern # 31

It’s best to think twice before moving pawns that form the king’s shelter, but often people play f2-f4 (f7-f5) in order to gear up their rooks and f pawns against the opponent’s king. Unfortunately that weakens the a2-g8 (a7-g1) diagonal. So whenever your opponent plays such moves you should think about possibilities of smothered mate, a Greco mate or the mate along the h file, as usually the king hides on h8 (h1) after a check along that diagonal.

Sidney Paine Johnston against Frank James Marshall in 1899

Q: In this position Marshall has weakened the a2-g8 diagonal but on the other hand it is closed by the e6 & d5 pawns. So White played 11.cxd5 and black replied with 11…exd5 as Marshall was relying on the discovered attack after White’s Nxd5.
Was it a good idea?

It turns out to be a bad one because White’s light square bishop can use it with devastating effect. Please try to calculate this position yourself first then check what happened in the game:

12. Nxd5!

Opening up the diagonal.


13. Bc4!!

I think black missed this intermediate move now white is ready to use this diagonal. If 13.Nxd4 then Black gets satisfactory game after 13…Bxd5



Here Black has to surrender the piece in order to prevent himself from immediate loss.


Now what? Can you checkmate Marshall in few moves?


This double check leads to checkmate

16. Ng6+ hxf6

Opening up h file leads to mate on next move

17…Qh4 18.Rxh4#

Here White has sacrificed the knight in order to open up h file which is very common with this theme.

Ashvin Chauhan