The Chess Coach by Sunil Weeramantry Bishops of Opposite Colors Positions that feature bishops of opposite color are frequently dismissed by the average player as being drawn. This may be true in endgames with only bishops and pawns on the board, as passed pawns will have difficulty advancing on to the color of the opposing bishop. However, nothing can be further from the truth in the middle-game when queens are added to the mix. Indeed, such positions will invariably favor the attacker. An active bishop that targets weaknesses around the enemy king can be all-powerful because the opposing bishop is unable to challenge its dominance over squares of one color. To understand how dangerous a middle-game with bishops of opposite colors can be to the defender, let us look at the final stages of a direct attack. In Padevsky-Larsen, Moscow, 1956, Black's forces are already poised for the attack. White's queen is out of play; and his bishop is not particularly useful either. All that remains for Black to do is to achieve the final breakthrough. (See diagram) White: Kg1, Qa7, Re1, Bb6; pawns - a2, b2, g2, h2 Black: Kg8, Qf5, Rd2, Bc4; pawns - b5, e6, f7, g7, h6. Larsen realizes that a destructive sacrifice will leave White in a precarious position, unable to repulse an attack on the light squares. Accordingly, he unleashes a powerful rook sacrifice to expose the white king. 1...Rxg2+! 2. Kxg2 Bd5+. The white king is unable to flee as 3. Kg1 is met by 3...Qg4+ 4. Kf2 Qf3+ 5. Kg1 Qg2 mate; and 3. Kg3 meets a similar fate after 3...Qf3+ 4. Kh4 g5 mate. 3. Re4. Even giving back material does not save White. Larsen has calculated correctly that his sacrifice leads to a forced win. 3...Bxe4+ 4. Kg1 Qg5+ 5. Kf2 Qd2+ 6. Kg3 g5 7. Qb8+ Kh7 8. Bf2 Qd3+ 9. Resigns. 9.Kg4 is answered by 9...Qf3 mate. Larsen is, of course, one of the greatest players ever. He will be remembered by future generations as the leader of the Rest of the World team that narrowly lost a historic match to the USSR in 1970. For a great player such as Larsen, the actual execution of the attack is relatively simple. What is more challenging is being able to reach such a position in the first place. Therein lies the real mark of the master. Our next example explores the earlier stages of a combination and examines how such an attack is created. This position was reached in the game Tartakower-Przepiorka, Debreczen, 1925. (See diagram) White: Kg1, Qe2, Rd1, Rf2, Bg5; pawns - d3, f4, f6, g2, h2 Black: Kg8, Qd5, Ra3, Rc8, Bb7; pawns - a7, b6, e6, f7, g7, h7 Tartakower has boldly sacrificed his a3 pawn to pursue a king-side attack. At first sight, this strategy appears misguided as not one of White's major pieces is presently in good attacking position. 20. f5! A pawn break that seeks to open lines to the enemy king. 20...exf5 21. Qe7. Suddenly, the white queen occupies a commanding post deep inside enemy territory and creates multiple threats. 21...Ra4. Black moves the rook out of danger and threatens ...Rg4. Tartakower points out that if the rook had made a more passive move such as 21...Rac3, he would have continued with 22. fxg7 intending to set up a mating attack on the dark squares with Bh6 and Qf8+. 22. Rc1 Rxc1+ 23. Bxc1 Bc6. This is the only reasonable way to prevent the back rank mate as 23...Qc5 loses a rook to 24. Qe8+ Qf8 25. Qxa4. 24. fxg7 Kxg7. There is nothing better. 24...Qc5 is refuted by 25. Qd8+ Kxg7 26. Bb2+ Kg6 27. Qf6+ Kh5 28. Qxf7+ with mate to follow. (See diagram) 25. Bh6+! Resigns. A beautiful conclusion. 25...Kxh6 loses to 26. Qf6+ Kh5 27. Rxf5+ Qxf5 28. Qxf5+ Kh6 29. Qf6+ Kh5 30. Qxc6 winning material. Appreciating the attacking potential inherent in positions with bishops of opposite colors will enable the strong player to steer a game in the right direction. Consider, for instance, the decision confronting Taimanov in his encounter with Averbakh in the Candidates Tournament, Zurich, 1953. (See diagram) White: Kg1, Qh6, Ra1, Re1, Bb2, Bd3; pawns - c4, e3, e5, f2, g2, h2 Black: Kg8, Qd8, Rf8, Rc7, Bb7, Ne4; pawns - b6, c5, e6, f7, g6, h7 Taimanov, playing white, had to decide whether to keep the bishop pair or to trade off into an opposite color bishop middlegame. He chose the latter, judging correctly that the dark square weaknesses around the black king would generate good attacking chances. The game continued as follows: 22. Bxe4 Bxe4 23. Red1 Rd7 24. Rd6 Bb7. Capturing on d6 with 24...Rxd6 will activate the white bishop. If Black then attempts to block the diagonal with ...f6, the white rook will penetrate to the seventh rank with devastating effect. 25. R1d1 Rxd6 26.exd6 f6 27.d7! As pointed out by Pachman in Complete Chess Strategy, White is now threatening 28.Qxf8+! Kxf8 29. Bxf6 with a winning position. If Black avoids this with 27...Rf7, he still loses after 28. Qh3 f5 29. Qh6 Rxd7? 30. Qg7+! An elegant finish. 27...Bc6 28. h4. While Black is attending to the d7 pawn, White opens a second front, shattering the already weakened king-side. 28...Bxd7 29. h5 gxh5 30. e4 e5 31. f4. This opens the diagonal for the b2 bishop which joins the attack with deadly force. Its counterpart, on the other hand, is quite ineffective despite its apparent mobility. 31...exf4 32. Rd6 Qe8 33. Bxf6 Rf7 34. Rd5 Resigns. Bishops of opposite colors can also lead to positions where one player maintains total control of the game because he has the more active bishop. In theory, his opponent may well be able to hold a passive position and to withstand a direct attack. In practice, however, the pressure of having to defend accurately for any significant length of time often takes its toll on the defender. This point is driven home quite effectively in Karpov-Nunn, London 1982, where the following position was reached after Black's 32nd move. (See diagram) White: Kh1, Qe3, Rd1, Rg2, Bd5; pawns - a5, b4, c4, f4, g3, h2 Black: Kh8, Qf6, Rc7, Re8, Bg7; pawns - a6, b7, d6, e4, f5, h7 The simple fact that White's bishop occupies a good attacking position while Black's bishop is reduced to a passive role gives White a clear initiative. Furthermore, only White has any pawn breaks available to him, specifically on b5 and g4. All this ensures that White is in complete control of the game. 33. g4. Karpov decides to open the kingside immediately. Although this move does put Black under considerable pressure, Nunn feels that Black should be able to hold the position with careful play. He suggests that White should push 32. b5 which would leave Black with an isolated pawn on the queenside. 33...fxg4 34. Rxg4 Qc3 35. Rg3 Qxb4. According to Karpov, White would win if Black traded queens with 34...Qxe3. His analysis runs as follows: 35. Rxe3 Rce7 36. b5! Bh6 37. Rf1 Rf8 38. Rxe4 Rxe4 39. Bxe4 Rxf4 40. Rxf4 Bxf4 41. Bxb7 and the endgame is won despite bishops of opposite colors. White now builds up tremendous pressure against Black's king. 36. Rdg1 Qb2. This stops White's threat of Qd4, sacrificing the queen for mate on g8. 37. Rg5 Qf6 38. R1g4 Qa1+ 39. Kg2 Qb2+ 40. Kh3 Rce7 41. f5 Qf6? Nunn explains that his sealed move is too passive. 41...Qa1 staying on the long diagonal and threatening ...Qf1+ gives Black some drawing chances. From this point on, White's attack proves unstoppable. 42. Rh5 Rf8 43. Rgh4 h6 44. Rg4. Unfortunately for White, he cannot take on h6 immediately as 44. Rxh6+ is refuted by 44...Bxh6 45.Rxh6+ Qxh6+ 46. Qxh6+ Rh7 pinning the white queen. 44...Re5 45.Rgg5 Rc8. (See diagram) 46. Kg4! A remarkable move. The king takes over the defense of f5 to enable the rook to penetrate to g6. 46...Kh7 47.Rg6 Qf8 48. Qg5 Qxf5+. Desperation. 49. Qxf5 Rxf5 50. Rxg7+ Kxg7 51. Rxf5 Resigns. In going over this game, one point becomes abundantly clear. Defending an opposite color bishop middle- game with queens on the board is definitely not a pleasant experience.