# Philidor Defence: Exchange Variation 4. Nxd4
### Overview

In the Exchange Variation of the Philidor Defense, Black opts to relieve the central tension immediately with 3...exd4. This move captures White's d4 pawn with Black's e5 pawn. In response, White has the option to recapture the pawn on d4. The most logical recapture is with the knight, 4. Nxd4, positioning the knight centrally.
After White recaptures with the knight, Black has a popular move, 4...Nf6, which targets White's e4 pawn. To defend this pawn, White often develops another piece, the queen's knight, to c3 with 5. Nc3.
An interesting alternative for Black after 4. Nxd4 is the move 4...c5. This puts immediate pressure on the centralized white knight. White would need to decide how to respond, either by relocating the attacked knight or creating a counter-threat elsewhere on the board.
The Exchange Variation with Nxd4 in the Philidor Defense leads to rich positional play. Black relieves central tension early on, but the resulting positions offer ample opportunities for both sides to create imbalances and fight for an advantage.

## Theory table

For explanation of theory tables, see theory table and for notation, see algebraic notation. .
1. e4 e5 2. Nf3 d6 3. d4 exd4 4. Nxd4
| | 4 | 5 | 6 | 7 | 8 | 9 | |
| Exchange Variation 4. Nxd4 | Nxd4 Nf6 | Nc3 Be7 | Bc4 O-O | O-O Nxe4! | Nxe4 d5! | Bd3 dxe4 | = |
| Exchange Variation 4. Nxd4 | ... .... | ... ... | Bf4 O-O | Be2 Nc6 | O-O Re8 | | = |
| Exchange Variation 4. Nxd4 | ... .... | ... ... | ... ... | ... ... | Qd2 Nxd4 | Qxd4 | +/= |
| Exchange Variation 4. Nxd4 | ... .... | ... ... | ... ... | ... Re8 | Qd2 Nc6 | O-O-O | +/= |
| Exchange Variation 4. Nxd4 | ... .... | ... ... | ... ... | Qd2! d5 | Ndb5 Bb4 | O-O-O | +/= |
| Exchange Variation 4. Nxd4 | ... .... | ... ... | ... ... | ... Nc6 | O-O-O Nxd4 | Qxd4 | +/= |
| Exchange Variation 4. Nxd4 | ... .... | ... ... | Be2 O-O | Bf4 Re8 | Qd2 | | +/= |
| Exchange Variation 4. Nxd4 | ... .... | ... ... | ... ... | O-O Re8 | f4 | | +/= |
| Exchange Variation 4. Nxd4 | ... .... | ... ... | ... ... | ... ... | Re1 | | +/= |
| Exchange Variation 4. Nxd4 | ... .... | ... ... | g3 d5 | e5 Ng4 | Bg2 Nxe5 | Qe2 | +/= |
| Exchange Variation 4. Nxd4 | ... .... | ... ... | ... O-O | Bg2 Re8 | O-O | | +/= |
| Exchange Variation 4. Nxd4 | ... .... | ... ... | ... ... | ... ... | ... O-O | O-O | +/= |
| Exchange Variation 4. Nxd4 | ... .... | ... ... | ... O-O | Bg2 Re8 | O-O Bf8 | h3 | +/= |
| Exchange Variation 4. Nxd4 | ... Nc6 | | | | | | = |
| Exchange Variation 4. Nxd4 | ... c5 | Nf3 Nc6 | Nc3 Be7 | Bf4! Nf6 | Qd2 Be6 | Ng5! | +/= |
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## References

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

* 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.
* Marsh, Sean (ChessAble) (2021). Chess Opening Basics: The Philidor Defense.
* Prem, Krishna (2012). Chess openings - Philidor Defence.
* The Chess Website (2012). Philidor Defense - Chess Openings.
* Solomon, Ruddell (TheChessGiant) (2021). Chess Openings: Learn to Play the Philidor Defense!.