A pair of Bishops is a well-known positional plus. Bishops are long-range pieces and have enormous attacking potential when placed correctly. While the advantages of having a pair of Bishops in the open positions are well known, most chess positions are semi-closed. The logical conclusion is that the side that has a pair of Bishops should try to open the game.

Bishops thrive on open diagonals where they have some targets to attack. They also provide great support for a moving pawn-mass. Let’s take a look at the following examples.

Boleslavsky-Scherbakov, Moscow 1942

WHITE TO MOVE

White has Bishop pair, but since the position is semi-closed, his advantage does not seem to be serious. However, such an impression is incorrect. White has serious pressure here and the opening variation this came from practically went out of practice.

What should White do? He must find some way to open the position. A good way of doing that is advancing pawns in order to make a pawn contact and pawn exchanges, freeing up more space and opening up the Bishops’ diagonals. A second important thing is placing pawns in such way that it would limit the opponent’s Knights. Since the central pawns are more or less static at the moment, the wing pawns on the queenside are ideal candidates for space-gaining advances.

1.a4! Ke7

The King is frequently left in the center in positions like this one. Since there is little potential for attack in the center, the King may stay there and later, after some more exchanges, it can move forward. This may eventually save some time, since after castling the King is far away from the center and in many cases has to go back there later. This conclusion does not mean that castling should be delayed! It only applies to opening lines where Queens are exchanged early in the opening.

2.Rfd1 Rd8

Both sides established presence along the only open file. In case of 2...a5? Black will have trouble defending his a-pawn after 3.Nb3, threatening Be3-b6.

3.Ba2!?

Another good alternative was 3.a5, in that case 3...Nd4? runs into 4.c3 and if 4...Nc2? 5.Bc5+ Ke8 6.Rac1 when the Knight is trapped. After 3.a5, White intends to play b2-b4 and Nd2-b3, followed by Nb3-c5 and b4-b5 at some point.

3...f6

Black strengthens the e5-square, but makes his opponent’s light-squared Bishop more influential in view of the weakened position of the e6-Knight. Once again, 3...Nd4? is not good: 4.Nc4! Nxc2 5.Bc5+ Ke8 (5...Kf6 6.Rxd8 Nxa1 7.Nd6 wins a piece) 6.Rxd8+ Kxd8 7.Rd1+ with a very strong attack.

4.Nc4 b6

Black already experiences some difficulties. White is about to overtake the d-file by simply exchanging Rooks on d8, while Black is yet to develop his queenside pieces. The idea of 4...b6 is to play ...Bc8-a6, but it makes additional targets for White’s dark Bishop.

5.Rxd8

While this move hardly spoils anything, more precise was 5.a5! and if 5...b5, then 6.Rxd8 and here both 6...Nxd8 7.Bc5+ followed by Nc4-d6, or 6...Kxd8 7.Rd1+ Ke7 8.Nd6 would give White a large advantage due to the very powerful dark-squared Bishop.

5...Nxd8 6.a5 Be6!

This is the difference. Black managed to bring his Bishop out and now 7.axb6? axb6 is great for him, thanks to the pin against the a2-Bishop.

7.Bb3 Bxc4?

Black will suffer forever after this. Better was 7...b5 8.Bc5+ Kf7 (8...Kd7? 9.Rd1+ Kc7 10.Nb6! axb6 11.Bxb6+ Kb7 12.Bxd8 Bxb3 13.cxb3 gives White a winning game) 9.Nd6+ Kg8 10.a6 Bxb3 11.cxb3 Ne6 promises Black some chances. Here 12.Rc1? allows 12...Nhf4! 13.Rc2 Rd8! 14.Nb7 Rd1+ 15.Kf2 Ra1!, which is annoying. Better is 12.Be3, though 12...Nhf4 still leaves Black with some chance for a successful defense.

8.Bxc4 b5 9.Bc5+ Ke8 10.Bg8

While the center of the board remains closed, White’s Bishops have found very comfortable diagonals. The Black pawns are very weak, and the d-file will soon be occupied by White. Black manages to save himself from immediate loss with some great defensive play.

10...Nb7! 11.Bf2 a6

Now 12.Bxh7? loses a piece after 12...Kf7 13.Rd1 Rd8 14.Rxd8 Nxd8, but Boleslavsky takes d8-square under control.

12.Bb6! Kf8 13.Bb3!

White avoids a nasty trap. Here 13.Bxh7? Kg7 14.Rd1 meets 14...Rf8! 15.Rd7+ Rf7 and the light Bishop is trapped.

13...Ke7?

This move bring the King over to defend d7, but it allows White to attack on the queenside. The only move was 13...Nf4! and if 14.Rd1, then 14...Ne2+ 15.Kf2 Nd4! 16.Bxd4 cxd4 17.Rxd4 Ke7! 18.Ba2 Nxa5. In that case, while White has some edge after 19.f4, Black would retain serious chances for a draw.

After 13…Nf4, possible is 14.Kf2 Ke7 and, unlike the actual game, 15.c4 b4 16.c5 is not good in a view of 16...Nd3+.

14.g3!

A very important move. Now Black’s Knight has to go back to g7, giving White enough time to attack on the queenside.

14...Ng7 15.c4!

Now 15.cxb5 cxb5 (15...axb5 16.a6) 16.Bd5 is a serious threat.

15...Rc8 16.Rc1 b4 17.c5!

This move opens the light Bishop and cuts Black’s b-pawn off from the rest of his pieces.

17...Nd8

Here 17...Ne6 meets 18.Bxe6 Kxe6 19.Rc4 b3 20.Rc3 and White wins a pawn.

18.Bc4

Here 18.Rc4 would win a pawn, but after 18...Nde6 19.Rxb4 Nd4 20.Kf2 Nxb3 21.Rxb3 Ne6 Black would be able to put up a fight. Instead, Boleslavsky plays for domination.

18...Ra8 19.Kf2 Nde6 20.Ke3 Nd4 21.f4!

Black has managed to regroup his pieces and even installed his Knight on d4. Still, the a- and b-pawns are very weak and his Rook is paralyzed on a8. Using this situation, White starts his attack on the kingside. Black is helpless to stop it.

21...Nge6 22.Rf1!

Black has almost no moves! Here fxe5 or f4-f5 are in the air.

22...Nc2+ 23.Kd3 Ncd4 24.f5!

This move extends the influence of the light Bishop.

24...gxf5

In case of 24...Nf8 25.Bc7! is very strong, threatening Bc7-d6+ and f5xg6. For instance, 25...gxf5 26.exf5 Nd7 27.Bd6+ Ke8 28.g4, threatening g4-g5.

An attempt to lock up the game with 24...Ng7 25.g4 g5 fails in a view of 26.h4 h6 (26...gxh4 27.Rh1 Nf3 28.Ke3 Ng5 29.Rxh4 also gives White an advantage, since the Rook can go back to h1 and then to d1) 27.Rh1, threatening h4xg5.

25.exf5 Ng7 26.Ke4

White avoids 26.g4 h5 27.h3, since ...hxg4 and ...Ra8-h8-h3 may be possible at some point.

26...Ne8 27.g4

Now 27...h5 meets 28.g5! fxg5 29.Kxe5 and f5-f6+ wins.

27...Nc2 28.Rf2 Nd4

Black is waiting for his opponent to initiate the action, since not much else can be done. White can’t improve his position much – all his pieces have great positions. Therefore, it’s time to look for a break.

29.g5! Nb5

Even worse is 29...fxg5 30.Kxe5 Nb5 31.f6+ Kf8 32.Rg2! h6 33.h4 and White wins.

30.Bxb5 axb5 31.h4!

Here 31.gxf6+? meets 31...Nxf6+ and 32.Kxe5?? loses to 32...Ng4+. Accuracy is always important.

31...Kf7 32.Rd2 Ke7

Black is barely holding and any move would make his position even worse.

33.b3! Rb8 34.a6 Rc8 35.a7 Ra8 36.Rd8!

A nice way to close the show by Boleslavsky! Now 36...Rxd8 37.Bxd8+ wins.

36...Nc7 37.Bxc7 Rxa7 38.gxf6+, 1-0.

Bishops are always great when there is a moving pawn pair, or three connected pawns. In such cases Bishops stand behind the pawns, supporting them from a distance, or attack squares ahead of such pawns, supporting their move forward.

Petrosian-Lilienthal, Moscow 1949

WHITE TO MOVE

In this position the center is closed, but there are some open diagonals. White’s goal here is to make the game more open, plus he should also keep his eye on the kingside. Petrosian starts shaking his opponent’s position up.

1.f4! e4?

Almost a decisive mistake! Necessary was 1...Nf7 in order to meet 2.fxe5 with 2...Nxe5 and if 3.Be2, then 3...Rae8, consolidating in the center. It seems like Black is doing the right thing by keeping the game closed, but the possibility of g3-g4 makes the e4-pawn vulnerable.

2.Be2 Rc8

In case of 2...Nf7 3.Rab1 Black has to play 3...Rab8, putting his Rook in a passive position. White can also later play Rb1-b2, Re1-b1 and push the a-pawn forward in case of ...b7-b6.

3.c4 Ne8

This Knight is going to f6, where it will support the e4-pawn. In case of 3...h5? 4.Bc3 Black would have trouble defending his h5-pawn.

4.h3! Nf6 5.g4

White is now threatening 5.g5 Ne8 6.h4, followed by h4-h5, Bd2-g3, totally immobilizing his opponent’s pieces.

5...fxg4 6.hxg4 Rc7

Black now threatens 6...Nxg4! 7.Bxg4 Rg7, but Petrosian avoids it easily.

7.Kf2! h6 8.Rh1

The pressure on the h-pawn is very strong and Black tries to confuse things with a pawn sacrifice.

8...e3+ 9.Bxe3 Ne4+ 10.Kg2

Here 10...Re7 meets 11.Bd3 and if 11...Ng3, then 12.Rhe1!

10...Nf7 11.Bd3 Re7 12.Rae1

White brings his last piece into the game and threatens Be3-c1, repositioning his Bishop to a more active diagonal.

12...Rfe8 13.Bc1 Nc3

Lilienthal attempts a counterattack along the e-file and against the a4-pawn, but since he has no available squares for his Rook in White’s position, this attack has no chance of success.

14.Rxe7 Rxe7 15.a5 b6 16.axb6 axb6

17.Bd2!

This is more precise than 17.Bb2 Ne2! 18.Kf3 Nd4+ 19.Kf2 Ra7 and Black can hang on little longer.

17...Ne2 18.c3!

Petrosian traps the Knight and the game is immediately over.