Bad endgame

So I played this game against someone ranked a couple of hundred points higher than me.  Was happy until the end of the game.  I deliberately exchanged down to try and get an endgame with an extra pawn.  This happened, and because I am not great at endings, I lost!

In writing down my analysis, I think I lost the game when I castled.  At that stage, I now think it wasn't needed, and left my King well away from the action.

Also some errors with the pawns afterwards.

Any thoughts appreciated.

Here is what Rybka has to say:

Note at move 17 you could have won a piece by force

Ah, I certainly did not see that.  I think I had decided that I wanted to see how I was with an extra pawn, and lost sight of actually trying to win.

yes did you resign here? why?

but even if he didn't know, he should have played on...

It can be debated whether there's something better than 20... 0-0 but I don't think it's too bad and you certainly didn't loose because of that. If the centre would be more closed then directly centralizing the king would most probably be best but here the central files are open and all rooks still on the board so black needs to be somewhat carefull.  Personaly I would also probably play 0-0 (altough I might also consider 0-0-0). Black should be the only one playing for win after that.

However later on you should try to bring the king closer to centre. For example 25... Kf8 instead of 25... Rd7 (but again black is still the only one playing for win after Rd7 also).

I think he may have loss on time? I am terrible with endgames as well; with winning positions, given games away.

Anyway, Rybka did all the work already, but I was thinking when playing through the game that 17)...Be6 would be better than just trading, it's a free move. After Qd3, Bf5, Qc4, b5 (The actual suggestion was b5 first).

Haven't looked at the game, but as pointed by others, the final position is drawn. So you may want to look at some basic pawn endgames (K+p vs. K)

Bugger.  I thought it was a stone cold loss - also I think I was in a bad mind set as I knew I had played quite well and stuffed it up.

Am trying to learn more from my losses though, and I know my endgames are weak.  Thanks for the comments.  Interesting that the castling has brought out mixed opinions.

...and in the pawn endgame, centralizing the king is important : I think the position after the rook trade should be won for black.

Hmm...

So my lessons are:

Castling after a few pieces are off the board is perhaps not as cut and dry a good idea as early on in the game.

I really need to get better at playing with pawns in the endgame.

I missed a chance to go a full piece up - need to examine positions more deeply.

Cheers all.