[Event "USSR Championship"] [Site "?"] [Round "0"] [White "Boleslavsky"] [Black "Mikenas"] [Result "1-0"] [ECO "B10"] [Opening "Caro-Kann: 2.Nf3"] {Diamond cut diamond} 1. e4 c6 2. Nf3 d5 3. Nc3 Bg4 4. h3 Bxf3 5. Qxf3 e6 6. d3 Nf6 7. g3 Bb4 8. Bd2 d4 9. Nb1 Bxd2+ 10. Nxd2 Qa5 11. a3 Nbd7 12. Qe2 h5 13. h4 Ng4 14. Bh3 Ndf6 15. O-O O-O-O 16. Nc4 Qc7 17. e5 Ne8 {WHITE TO MOVE:} 18. a4 $1 (18. Bxg4 hxg4 19. Qxg4 b5 {removing the guard}) 18... f5 19. exf6 Nexf6 { WHITE TO MOVE:} 20. b4 $1 {In accordance with the requirements of the position that both sides must pursue the attack with maximum vigor. In such positions a pawn more or less means nothing, and White doesn't capture on e6 as the opened e-file would only help Black} (20. Qxe6+ {Opened e-file helps Black attack}) 20... Rhf8 21. b5 Kb8 (21... c5 22. a5 Qf7 23. a6 b6 24. f3 { White wins at least a pawn while holding a powerful initiative}) 22. bxc6 Qxc6 23. Bg2 Qc7 (23... Nd5 24. Rab1 Nc3 25. Qe1 $1) 24. Rab1 { Illustrative of "converging lines"} 24... Nd5 25. Qxe6 {At precisely the right moment. White is not interested so much in winning the pawn as in the resulting attack against Pd5} 25... Rxf2 26. Rxf2 Qxg3 { WHITE TO MOVE: The best defence?} 27. Rf3 $1 Qh2+ 28. Kf1 b6 { WHITE TO MOVE: Attack or defend?} (28... Qxh4 29. Rxb7+ Kxb7 30. Rf7+ Kb8 31. Qc6 Nde3+ 32. Ke2 $18) 29. a5 $1 Nf4 {The drama reaches its climax. Unless there is a forcing line now, White will have to take a perpetual check} 30. Rxb6+ axb6 31. Qxb6+ Kc8 32. Qc6+ Kb8 33. Qb5+ Kc7 { WHITE TO MOVE: How to attack and defend?} (33... Ka7 34. Qb6+ Ka8 35. Rxf4+ $18 ) (33... Kc8 34. Qf5+ $18) 34. Rf2 $1 {Combining attack and defence} 34... Rd5 (34... Nxg2 35. Rf7+) (34... -- 35. Qb7#) 35. Qb6+ Kc8 (35... Kd7 36. Qb7+ Ke8 37. Qb8+ Kd7 38. Qxf4 $18) 36. Qc6+ Kd8 (36... Kb8 37. Qe8+ Kc7 38. Qf7+ $18) 37. Qa8+ Ke7 38. Qb7+ Rd7 (38... Kd8 39. Qb8+) (38... Kf6 39. Qxd5 Nxf2 40. Qc6+ Kf7 41. Ne5+ $18) 39. Qe4+ Ne6 40. Re2 Kf8 41. Qxe6 Qf4+ 42. Bf3 Qxf3+ 43. Ke1 Nf6 (43... Qf7 44. Qxf7+ Kxf7 45. Ne5+ Nxe5 46. Rxe5 {Easy Rook ending}) 44. Ne5 Qg3+ 45. Kd1 Re7 46. Ng6+ $1 1-0