Against the King's Indian bishop, beware! do not open that big diagonal!

A few months ago I came across an amazing game in which Lev Alburt, playing Black, won against Vlastimil Hort, at a time when Hort was a top-10 player! The game was astounding, for Alburt sacrificed his Queen, but dominated the whole board! He made Hort look helpless!

One thing that stuck in my mind was the weakness of the c3 square, caused by the move b3.....

The Alburt game reminded of another spectacular game in which Kramnik plays b3, and the weakening of that c3 square proves fatal!

Now, these two games reminded me of two earlier games by Bronstein; two games from 1946, from the Moscow-Prague match.....these two games made Bronstein famous, and also put the King's Indian Defense on the map!

Both games feature a similar theme: White uses a system in which he plays b3 against the King's Indian, and Bronstein exploits that a1-h8 diagonal to the maximum!

This brings me to the final example of this blog: Gufeld's brilliant win against Smyslov!

Smyslov tries to dominate the board by playing b4, e3 and d4, but Gufeld breaks open the position, and then makes two consecutive piece sacrifices to gain the advantage!

I hope these games are a powerful reminder of how dangerous it is to open the a1-h8 diagonal against a King's Indian Defense formation!