Editing Philidor Defence (section)

===3...exd4===
The most common Black response is 3...exd4 which relieves the central {{chessgloss|tension}}, although it gives up the centre. After 4.Nxd4 Nf6 (4...d5 5.exd5, the [[Louis Paulsen|Paulsen]] Attack,<ref>Hooper & Whyld 1996, p. 293. ''Paulsen Attack''.</ref> continues 5...Qxd5 6.Qe2+ Be7 7.Nb5 Na6 8.N1c3{{chesspunc|+/{{=}}}} Paulsen<ref>Matanović 1997 (Vol C), p. 214, n. 19.</ref>) 5.Nc3, Black normally continues ...Be7 and ...0-0 (the [[Vladimir Antoshin#Philidor Defence|Antoshin Variation]]) and achieves a strong defensive position. A sample line is: 5...Be7 6.Bc4 0-0 7.0-0 c6, and the position is almost {{chessgloss|equality|equal}}. 

In this line Black can also [[fianchetto]] his bishop to g7, although this is uncommon. [[Bent Larsen]] tried this in a few games, including a [[draw (chess)|draw]] against [[Mikhail Tal]] in 1969.<ref>{{cite web |url=https://www.chessgames.com/perl/chessgame?gid=1139887 |title=Mikhail Tal vs. Bent Larsen, Eersel NED (1969) |website=[[Chessgames.com]] }}</ref>

Instead of 4.Nxd4, White can play 4.Qxd4, as Paul Morphy favoured, intending 4...Nc6 5.Bb5 Bd7 6.Bxc6 Bxc6 7.Nc3 Nf6 8.Bg5 followed by 0-0-0. This line was played in many 19th-century games.