Monday, August 16, 2010
A trap in the Kangaroo Defense
The opening 1.d4 e6 2.c4 Bb4+ is an unusual but perfectly sound defense. It can transpose to the Nimzo-Indian, Bogo-Indian, Dutch, Queen's Indian, or English Defense (1.c4 b6). It is sometimes known as the Keres Defense, since the young Paul Keres was fond of it, often as a prelude to a Dutch Defense. Watson and Schiller, in their excellent if suggestively titled The Big Book of Busts, call it the Kangaroo Defense for some reason. (Schiller is big on weird animal names for openings.) All minor piece interpositions are playable, but I've usually played 3.Nbd2, hoping to gain the bishop pair.
The above game is the second in which my opponent has found 3...d6??, losing either a bishop or a knight after 4.Qa4+! As this game illustrates, before moving a piece to an unguarded square you must always watch out for queen checks! For example, Qa4+ can vacuum up a knight on a5, a bishop or knight on b4, a knight on e4, a bishop on g4 (if ...e6 has been played, blocking the bishop's way home), etc. The theme of 1.Qa4+ (attacking a bishop on b4) Nc6 (forced to save the bishop) 2.d5 exd5 3.cxd5 winning the knight is a common one. It often fails if Black has a knight or a queen on f6 (allowing Black to save the day with 3...Nxd5 or 3...Bxc3+ 4.bxc3 Qxc3+ and 5...Qxa1, respectively).