Friday, December 25, 2009

GP Tactics: Endgame Oversight

I will be publishing some of the tactical problems, labeled with the “GP Tactics” tag,  that were data-mined from my own games, as described in this previous post
A tactics set generated from your own games not only provides variety in difficulty level, but variety in motifs.  For example, many of the problems involved endgame positions.
For the position below. Black seems to be making progress on the queenside.  Analyze and evaluate 1…Nb4:

Solution after the fold

1…Nb4? is a clear example of the principle: don’t exchange into a pawn endgame if you aren’t sure of the outcome.  2.Nxb4! Kxb4 and what I missed was 3.f5!,  a classic pawn breakthrough.  If 3…exf5, the black king is outside the square of the e5 pawn:4.e6!

A tougher defense is to get the defending king back in the square of the potentially passed e- and f-pawns, but White should still win: e.g. 40…c3+ 41.bxc3+ Kc5 42. f6 gxf6 43. exf6 Kd6 44. c4! a3 45. c5+ +-


Anonymous said...

Nb4 looks strong occupying a key square for Black's Q-side advance, but the ensuing exchange brings his king away from another critical square, e6, on which stands an isolated pawn, that alone blocks White's only fighting chance - his modestly advanced e-pawn.

1 ... Nb4?
2 Nxb4 Kxb4
3 f5!


Am I right?



p.s. 1...Nb4 aside, am I right to think Black winning assuming best play on both sides?

Grandpatzer said...

Rybka finds an even game before 38...Nb4, but I'm reluctant to accept a computer evaluation in this type of endgame position.