Game Spotlight: Positional Blunders

While I was inputting the games for the 61st Nairobi Chess Club Open Championship, I noticed one of the games had a well-known play mistake.  Unlike the blunders seen here, though, this one was instructive in that it was positional in nature.  So first, a few words about this type of thing.

A positional blunder is a play mistake that gives you a worse position.  It doesn’t lose right away, in that it doesn’t lose material or lead to a quick mate.  But it does give a lingering disadvantage for a long time.  This should lose given accurate play, but it’s quite possible to overcome a positional blunder (which is what happened in the Open Championship game — White made the blunder and still won the game).

Instead of looking at the Open Championship game, let’s look at how this particular blunder should go.  We’ll follow one of our Ugandan neighbours, in one of the games from the most recent Olympiad: