C41 Philidor Defense
C41 holds 44 named lines, all under the name Philidor Defense. It leaves C40 (King’s Knight Opening) with 2...d6. Material is no longer level at the end of 12 of its lines; the widest gap, two pawns in Black’s favour, comes in Philidor Defense: Lion Variation, Forcing Line. With 44 named lines it is the fourth-largest code of the 100 codes in volume C.
| # | White | Black |
|---|---|---|
| 1 | e4 | e5 |
| 2 | Nf3 | d6 |
Moves only C41 plays
Same as C40 up to 2.Nf3, then:
- 2...d6 The d-pawn advances to d6, covering c5 and e5, opening a line for the bishop on c8 and the queen on d8.
Lines filed under C41
All 44 share the start 1.e4 and then split two ways at Black’s move 1.
| Name | After the shared start | Plies | At the end |
|---|---|---|---|
| Philidor Defense | 1...e5 2.Nf3 d6 | 4 | |
| Philidor Defense | 1...e5 2.Nf3 d6 3.d4 | 5 | |
| Philidor Defense | 1...e5 2.Nf3 d6 3.Bc4 | 5 | |
| Philidor Defense | 1...e5 2.Nf3 d6 3.Bc4 Be7 | 6 | |
| Philidor Defense: Exchange Variation | 1...e5 2.Nf3 d6 3.d4 exd4 | 6 | Black +1 |
| Philidor Defense: Hanham Variation | 1...e5 2.Nf3 d6 3.d4 Nd7 | 6 | |
| Philidor Defense: Lopez Countergambit | 1...e5 2.Nf3 d6 3.Bc4 f5 | 6 | |
| Philidor Defense: Nimzowitsch Variation | 1...e5 2.Nf3 d6 3.d4 Nf6 | 6 | |
| Philidor Defense: Philidor Countergambit | 1...e5 2.Nf3 d6 3.d4 f5 | 6 | |
| Philidor Defense: Philidor Gambit | 1...e5 2.Nf3 d6 3.d4 Bd7 | 6 | |
| Philidor Defense: Bird Gambit | 1...e5 2.Nf3 d6 3.d4 exd4 4.c3 | 7 | Black +1 |
| Philidor Defense: Exchange Variation | 1...e5 2.Nf3 d6 3.d4 exd4 4.Nxd4 | 7 | |
| Philidor Defense: Morphy Gambit | 1...e5 2.Nf3 d6 3.d4 exd4 4.Bc4 | 7 | Black +1 |
| Philidor Defense: Nimzowitsch Variation | 1...e5 2.Nf3 d6 3.d4 Nf6 4.dxe5 | 7 | White +1 |
| Philidor Defense: Nimzowitsch Variation, Klein Variation | 1...e5 2.Nf3 d6 3.d4 Nf6 4.Bc4 | 7 | |
| Philidor Defense: Nimzowitsch, Locock Variation | 1...e5 2.Nf3 d6 3.d4 Nf6 4.Ng5 | 7 | |
| Philidor Defense: Philidor Countergambit, Zukertort Variation | 1...e5 2.Nf3 d6 3.d4 f5 4.Nc3 | 7 | |
| Philidor Defense: Steinitz Variation | 1...e5 2.Nf3 d6 3.Bc4 Be7 4.c3 | 7 | |
| Philidor Defense: Albin-Blackburne Gambit | 1...e5 2.Nf3 d6 3.d4 Bg4 4.dxe5 Nd7 | 8 | White +1 |
| Philidor Defense: Boden Variation | 1...e5 2.Nf3 d6 3.d4 exd4 4.Qxd4 Bd7 | 8 | |
| Philidor Defense: Exchange Variation | 1...e5 2.Nf3 d6 3.d4 exd4 4.Nxd4 Nf6 | 8 | |
| Philidor Defense: Hanham Variation, Sharp Variation | 1...e5 2.Nf3 d6 3.d4 Nd7 4.Bc4 Nb6 | 8 | |
| Philidor Defense: Larsen Variation | 1...e5 2.Nf3 d6 3.d4 exd4 4.Nxd4 g6 | 8 | |
| Philidor Defense: Lion Variation | 1...e5 2.Nf3 d6 3.d4 Nf6 4.Nc3 Nbd7 | 8 | |
| Philidor Defense: Hanham Variation, Delmar Variation | 1...e5 2.Nf3 d6 3.d4 Nd7 4.Bc4 c6 5.c3 | 9 | |
| Philidor Defense: Hanham Variation, Krause Variation | 1...e5 2.Nf3 d6 3.d4 Nd7 4.Bc4 c6 5.O-O | 9 | White castled |
| Philidor Defense: Hanham Variation, Schlechter Variation | 1...e5 2.Nf3 d6 3.d4 Nd7 4.Bc4 c6 5.Nc3 | 9 | |
| Philidor Defense: Hanham, Kmoch Variation | 1...e5 2.Nf3 d6 3.d4 Nd7 4.Bc4 c6 5.Ng5 | 9 | |
| Philidor Defense: Lion Variation, Shirov Gambit | 1...e5 2.Nf3 d6 3.d4 Nd7 4.Nc3 Ngf6 5.g4 | 9 | |
| Philidor Defense: Nimzowitsch Variation, Rellstab Variation | 1...e5 2.Nf3 d6 3.d4 Nf6 4.dxe5 Nxe4 5.Qd5 | 9 | |
| Philidor Defense: Nimzowitsch Variation, Sokolsky Variation | 1...e5 2.Nf3 d6 3.d4 Nf6 4.dxe5 Nxe4 5.Nbd2 | 9 | |
| Philidor Defense: Paulsen Attack | 1...e5 2.Nf3 d6 3.d4 exd4 4.Nxd4 d5 5.exd5 | 9 | White +1 |
| Philidor Defense: Hanham Variation, Steiner Variation | 1...e5 2.Nf3 d6 3.d4 Nd7 4.Bc4 c6 5.O-O Be7 6.dxe5 | 11 | White +1, White castled |
| Philidor Defense: Lion Variation, Bishop Sacrifice | 1...e5 2.Nf3 d6 3.d4 Nf6 4.Nc3 Nbd7 5.Bc4 Be7 6.Bxf7+ | 11 | White +1, check |
| Philidor Defense: Lopez Countergambit, Jaenisch Variation | 1...e5 2.Nf3 d6 3.d4 f5 4.Bc4 exd4 5.Ng5 Nh6 6.Nxh7 | 11 | |
| Philidor Defense: Philidor Countergambit, del Rio Attack | 1...e5 2.Nf3 d6 3.d4 f5 4.dxe5 fxe4 5.Ng5 d5 6.e6 | 11 | |
| Philidor Defense: Lion Variation, Lion’s Claw, with Bc4 and h6 | 1...e5 2.Nf3 d6 3.d4 Nf6 4.Nc3 Nbd7 5.Bc4 Be7 6.O-O h6 | 12 | White castled |
| Philidor Defense: Lion Variation, Lion’s Claw, with Be2 and c6 | 1...e5 2.Nf3 d6 3.d4 Nf6 4.Nc3 Nbd7 5.Be2 Be7 6.O-O c6 | 12 | White castled |
| Philidor Defense: Lion Variation, Delayed Bishop Sacrifice | 1...d6 2.d4 Nf6 3.Nc3 Nbd7 4.Nf3 e5 5.Bc4 Be7 6.dxe5 dxe5 7.Bxf7+ | 13 | White +1, check |
| Philidor Defense: Nimzowitsch, Larobok Variation | 1...e5 2.Nf3 d6 3.d4 Nf6 4.Nc3 Nbd7 5.Bc4 Be7 6.Ng5 O-O 7.Bxf7+ | 13 | White +1, Black castled, check |
| Philidor Defense: Philidor Countergambit, Berger Variation | 1...e5 2.Nf3 d6 3.d4 f5 4.dxe5 fxe4 5.Ng5 d5 6.e6 Bc5 7.Nc3 | 13 | |
| Philidor Defense: Lion Variation, Forcing Line | 1...e5 2.Nf3 d6 3.d4 Nf6 4.Nc3 Nbd7 5.Bc4 Be7 6.Ng5 O-O 7.Bxf7+ Rxf7 8.Ne6 | 15 | Black +2, Black castled |
| Philidor Defense: Lion Variation, Sozin Variation | 1...d6 2.d4 Nf6 3.Nc3 e5 4.Nf3 Nbd7 5.Bc4 Be7 6.O-O O-O 7.Qe2 c6 8.a4 exd4 | 16 | Black +1, both castled |
| Philidor Defense: Berger Variation | 1...e5 2.Nf3 d6 3.d4 exd4 4.Nxd4 Nf6 5.Nc3 Be7 6.Be2 O-O 7.O-O c5 8.Nf3 Nc6 9.Bg5 Be6 10.Re1 | 19 | both castled |
The road to C41
- 1.e4one earlier stop: B00
- 1...e5C20 King’s Pawn Game
- 2.Nf3C40 King’s Knight Opening
- 2...d6C41
The position after 2...d6
White has brought out the knight on f3; Black has not yet moved a knight or bishop. White could capture with Nxe5. White is to move and has 27 legal moves.
Closest boards in other codes
| Code | Line | Differs on |
|---|---|---|
| B07 | King’s Pawn Game: Maróczy Defense | four squares: g1, d2, f3, d4 |
| B50 | Sicilian Defense: Modern Variations | four squares: c5, e5, c7, e7 |
| C20 | King’s Pawn Game | four squares: g1, f3, d6, d7 |
| C42 | Petrov’s Defense | four squares: d6, f6, d7, g8 |
| C44 | King’s Knight Opening: Normal Variation | four squares: c6, d6, d7, b8 |
| C62 | Ruy Lopez: Steinitz Defense | four squares: f1, b5, c6, b8 |
| C34 | King’s Gambit Accepted: King’s Knight’s Gambit | five squares: f2, f4, e5, d6, d7 |