# Chess Opening Theory/1. e4/1...e5/2. Nf3/2...d6/3. d4/3...Nd7/4. Bc4/4...exd4
## 4...exd4

This is the only safe step in the minefield of traps. However, it looks strange, giving up the central strongpoint on e5, but Black remains solid. White usually plays Nxd4 and sets up one more trap. While White has a slight advantage, careful play is required to maintain the initiative and prevent Black from gaining counterplay. The position remains complex, with both sides considering various strategic options

###### White moves

* Qxd4: This move is beneficial for White as it threatens to play Nc3, supports the development of the knight to c3 by removing the pawn on d4, and threatens the black pawn on g7. The sequence 5. Qxd4 c6 6. Nc3 Qb6 7. Bf4 demonstrates how White can maintain the initiative, with the possibility of castling queenside on the next move (8. O-O-O).
* Nxd4: This move is also a viable option for White, as it wins material. However, White may lose some of the advantage gained earlier in the game. The move intends to follow up with either O-O or Nc3.

###### Black's main defensive ideas

* Playing ...Qb6 to support the pawn on d4
* Developing the knight to f6, threatening d5 or Ne5
* Moving the bishop to e7 to guard the key square g5 and protect the king.

## Theory table

| | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | |
| Hanham Variation |
| Hanham Variation | Nxd4 Ngf6 | | | | | | | | ⩲ |
| Hanham Variation | Qxd4! Ngf6 | Nc3 Be7 | Bf4 O-O | O-O-O Nb6 | Bb3 a5 | a3 | | | ⩲ |
| Hanham Variation | ... ... | ... ... | Bxf7+!? Kxf7 | Ng5+ Kg8?? | Qc4+ | | | | +/− |
| Hanham Variation | ... ... | ... ... | ... ... | ... Ke8 | Ne6 c5 | Qd1 Qb6 | Nxg7+ Kf7 | Nf5 | = |
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Bibliography
* Kasparov, Garry, & Keene, Raymond 1989 Batsford chess openings 2. ISBN 0-8050-3409-9.
* Kaufman, Larry (2004). The Chess Advantage in Black and White. ISBN 0-8129-3571-3.
* Panov, Vasily (1973). Teoría de Aperturas, Tomo I: Aperturas Abiertas - Aperturas Semiabiertas. ISBN 84-270-0132-0.
* Schiller, Eric (2002). Standard Chess Openings. ISBN 1-58042-048-6.

#### External links

* Chargemax Entertainment (2022). Chess For Beginners: Anand & Topalov easily get an edge vs Philidor Hanham variation.
* ChessBase (2023). Philidor Defence.
* Chess Openings for Beginners (2009). Philidor Defense: General Information.
* ChessPathways (2019). PHILIDOR DEFENSE.
* ChessPathways (2019). The Philidor Defense.
* Chess Simplified (2019). Philidor Defence.
* HangingPawns (2019). Introduction to the Philidor Defense.
* Hrishi Chavan (2022). Philidor Defence - Hanham Variation.
* Marsh, Sean (ChessAble) (2021). Chess Opening Basics: The Philidor Defense.
* Miodrag Perunovic (2019). Chess For Beginners: Anand & Topalov easily get an edge vs Philidor Hanham variation.
* Nicolas Skettos (2022). How To Beat The Philidor Defense - Hanham Variation - Black Lion - Chess Opening Traps.
* papachess.com (2024). papachess.com, Nimzowitsch's Unbeatable Weapon: Philidor Defense.
* papachess.com (2024). papachess.com, Philidor Defense: Nimzowitsch Variation, Rellstab Variation, move by move.
* Prem, Krishna (2012). Chess openings - Philidor Defence.
* Sean Lei (2020). My Precious "Philidor". Philidor and Lion Defence Chess.
* Solomon, Ruddell (TheChessGiant) (2021). Chess Openings: Learn to Play the Philidor Defense!.
* The Chess Website (2012). Philidor Defense - Chess Openings.