Paulsen Defense

After 2...Nf6 3. d3, Black keeps the queen's knight at home and plays 3...c6, so the c-pawn can support ...d5. The advance stakes out a broad center and gains time by hitting the bishop on c4. Black does not develop with ...Nc6 or ...Bc5, so the game cannot drift into the Giuoco Pianissimo or a Vienna. This makes the Paulsen Defense the most commonly played line of the Bishop's Opening with an identity of its own. It is also the reason some Black players unfamiliar with it choose ...Nc6 instead. Playing ...c6 on move three rather than move two, as in the Philidor Counterattack, appears to give Black better results.

The standard continuation is 4. Nf3 d5 5. Bb3, most often followed by 5...Bd6. White then concedes the center for the moment and tries to undermine it. 4. Nf3 is the most frequent reply, ahead of 4. Bg5, which pins the f6-knight, and 4. Nc3. The engine rates the position as level and also suggests 4. Bb3 and 4. Ne2. In online games, Black scores marginally better than White.