ecocodes
Volume D · Closed and semi-closed games‹ D17D19 ›
a1b2c3d4e5f6g7h8
Reference position · Black to move

D18 Slav Defense: Czech Variation, Classical System

D18 holds two named lines, all under the name Slav Defense. It leaves D17 (Slav Defense: Czech Variation) with 6.e3. When the reference line ends, Black is one pawn up on material. Black, to move in that position, has 39 legal moves, the third-highest count of the 10 Slav Defense codes. At 11 plies, its reference line is the third-longest of the 10 Slav Defense codes.

Score sheet
#WhiteBlack
1d4d5
2c4c6
3Nf3Nf6
4Nc3dxc4
5a4Bf5
6e3

The move that completes D18

The reference line of D19 plays all of these moves and continues beyond them; D18 is the position reached at 6.e3.

  1. 6.e3 The e-pawn advances to e3, covering d4 and f4, opening a line for the queen on d1 and the bishop on f1.

Lines filed under D18

Both share their first 11 plies, the whole reference line.

NameAfter the shared startPliesAt the end
Slav Defense: Czech Variation, Classical System(the shared start itself)11Black +1
Slav Defense: Czech Variation, Lasker Variation6...Na612Black +1

Slav Defense: Czech Variation, Lasker Variation

  1. 6...Na6 The knight leaves b8 for a6, opening a line for the rook on a8 and the queen on d8.

The road to D18

  1. 1.d4 … 4...dxc4seven earlier stops: A40, D00, D06, D10, D11, D15
  2. 5.a4D16 Alapin Variation
  3. 5...Bf5D17 Czech Variation
  4. 6.e3D18

The position after 6.e3

White has brought out the knight on c3 and knight on f3; Black the knight on f6 and bishop on f5. White has a half-open c-file; Black a half-open d-file. Black could capture with Qxd4.

WhiteBlackMaterial (pawn units)3839Minor pieces developed22Moves spent on pawns43Pawns on d4, e4, d5, e510Squares attacked in the other half58Doubled pawns01not castlednot castled

Codes that branch off from D18

The reference lines of one other code leave D18 from the position after 6.e3, each with its own moves.

CodeMovesReference line
D196...e6 7.Bxc4 Bb4 8.O-OSlav Defense: Czech Variation, Dutch Variation

Closest boards in other codes

CodeLineDiffers on
D16Slav Defense: Alapin Variationfour squares: e2, e3, f5, c8
D12Slav Defense: Quiet Variation, Schallopp Defensesix squares: b1, a2, c3, a4, c4, d5
D15Slav Defense: Three Knights Variationeight squares: a2, e2, e3, a4, c4, d5, f5, c8
D24Queen’s Gambit Accepted: Showalter Variationeight squares: a2, e2, e3, a4, f5, c6, c7, c8
D25Queen’s Gambit Accepted: Normal Variationeight squares: b1, a2, c3, a4, f5, c6, c7, c8
D45Semi-Slav Defense: Main Lineeight squares: a2, a4, c4, d5, f5, e6, e7, c8
D14Slav Defense: Exchange Variation, Symmetrical Lineten squares: c1, a2, e2, e3, a4, c4, f4, d5 …

Where lines continue from here

Three named lines filed under other codes pass through the position after 6.e3. All of them belong to the codes listed above.

Volume D

  1. 00
  2. 01
  3. 02
  4. 03
  5. 04
  6. 05
  7. 06
  8. 07
  9. 08
  10. 09
  11. 10
  12. 11
  13. 12
  14. 13
  15. 14
  16. 15
  17. 16
  18. 17
  19. 18
  20. 19
  21. 20
  22. 21
  23. 22
  24. 23
  25. 24
  26. 25
  27. 26
  28. 27
  29. 28
  30. 29
  31. 30
  32. 31
  33. 32
  34. 33
  35. 34
  36. 35
  37. 36
  38. 37
  39. 38
  40. 39
  41. 40
  42. 41
  43. 42
  44. 43
  45. 44
  46. 45
  47. 46
  48. 47
  49. 48
  50. 49
  51. 50
  52. 51
  53. 52
  54. 53
  55. 54
  56. 55
  57. 56
  58. 57
  59. 58
  60. 59
  61. 60
  62. 61
  63. 62
  64. 63
  65. 64
  66. 65
  67. 66
  68. 67
  69. 68
  70. 69
  71. 70
  72. 71
  73. 72
  74. 73
  75. 74
  76. 75
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  78. 77
  79. 78
  80. 79
  81. 80
  82. 81
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  84. 83
  85. 84
  86. 85
  87. 86
  88. 87
  89. 88
  90. 89
  91. 90
  92. 91
  93. 92
  94. 93
  95. 94
  96. 95
  97. 96
  98. 97
  99. 98
  100. 99

Open this line in the finderAll Slav Defense codes