A Janowski trap

The diagrammed position may look fairly modern but is taken from an old game between David Janowski and Ignatz Von Popiel, played in the last round of the Deutsche Schachbund congress at Hannover in 1902. It is White to play.

There are many situations in chess where the player on move has a positional advantage as well as an opportunity to start a tactical sequence. There is a temptation to think that such tactical sequences must end favourably for the player who starts with the advantage. This is not always true, the Janowski-Von Popiel game being a case in point.

As a confirmed representative of the combinative school, David Janowski decides it is time for White's centralised army to exploit Black's inferior development. His chosen method contains a very deep tactical point, but some analysis reveals that Black could have defended himself.

1.e5!? dxe5 2.Bxe5 Qb7 3.Bxf6!?
Janowski was fond of the two bishops, but also knew when to give one of them up.
3...Bxf3?
Von Popiel falls into Janowski's far-sighted combinative trap. Correct was 3...Bxf6! 4.Nd5 Kg7! White gains little from exchanging on f6, so the conclusion is that Black has managed to equalise.
6.Bxg7! Bxd1
There is no turning back. If 6...Kxg7 7.gxf3 and White is a piece up.
7.Bh6 Bxc2?!
Black had to acquiesce to the loss of material. After 7...e5 8.Rxd1 he will continue to suffer, but after his bishop move things end very quickly.
8.Qe5!
A very nice concluding blow, which threatens mate on the move. The only defence is 8...f6 but it costs Black his queen after 9.Qe6+ Kh8 10.Qf7 Rg8 11.Rxe7 Qxe7 12.Qxe7. Von Popiel resigned after 8.Qe5 and thus Janowski won the tournament.