A bizarre moment in a recent OTB game

I missed a very simple and quick win in this position in a tournament last weekend (White to move).

The game began as an English Hedgehog where I was very intentionally trying to do my best Ulf Andersson impersonation.

I had spent the whole game implementing the plan of controlling the d-file, putting an iron lock on d5, and ruling the light squares. Sometimes I get so caught up in the positional/strategic side of things that I forget the simple stuff.

A few moves later we ended up in this position (Black to move):



I got up and went to the restroom, thinking I have finally wrapped up a very intense game. When I returned to the board, my opponent's queen was on c5!

I was in shock, and I sat there thinking "How on earth could I have missed that?" I have had some bad tactical lapses in the last 3 months, and I just assumed that I had somehow screwed up again, not even considering that my opponent might have played an illegal move. It flustered me, and we ended up with me swindling a draw in a knight vs bishop ending.

I did not discover this until the next day when I was showing the game to a friend (ocean64 on the site here). I thought then that perhaps I had messed up the notation, and that my memory was faulty. I asked my opponent if he would verify the score with his scoresheet, and he had the same thing I did!

He was very embarrassed- we both were, for sharing a hallucination- and I am sure that he did it by accident, as he could easily have said that he did not have the score.

It was a very intense game, and we were one of the last boards in the room still playing when it ended. It is most certainly one of the most bizarre games I have played.

Moral: It's not always the guy going to the restroom that you have to watch!

My only strange experience of going to the toilet during a chess game was much happier for me - I went to the toilet when I was in a worse but not quite losing position and when I returned I found that the board had been tidied away and my opponent was nowhere to be seen. When I finally tracked him down it turned out that he had played a blunder, resigned, handed in the result to the controller and stormed out of the room, too furious with himself to consider that I wouldn't know what had happened in my absence!

Hi Paul,

that's bad luck you had there. I play mostly online, so I can't know the feeling, but it must feel sour afterwards.

I think it's one of the downsides of short-hand algebraic notation. You only have a list of to-squares, not the from-squares. It's also hard to set-up a position from the middle- or endgame, because the notation doesn't provide positions, just moves. Checking 3fold repetition must be hard also.

I'm guessing that illegal castling occurs on a regular basis as well.

Your quick and simple win is Qf8#, right? :-), just joking. I'm actually thinking of Ra5, am I right?

Originally posted by tvochess
I'm guessing that illegal castling occurs on a regular basis as well.

Originally posted by Fat Lady
I was once asked by a reigning British junior champion why ChessBase wouldn't allow her to enter the moves to a game she had just won and it turned out she (as Black) had played Kxd8 and Ke8 early on in the game and then much later castled kingside. ChessBase balked at that, which I think is a bug because illegal moves do happen and it should be able to accept them.

Originally posted by tvochess
I think it's one of the downsides of short-hand algebraic notation. You only have a list of to-squares, not the from-squares.

I see the point of being able to enter and access even illegal games in a database, but the management of the database should treat them separately. You don't want the statistics to include results from illegal games, do you?

Does any of you know how often these kind of illegal moves occur that are only discovered after the game?

Originally posted by SwissGambit
The from-squares are all there; they are the to-squares of the previous moves.

Originally posted by tvochess
I know they are there, but you have to look at all previous moves. It's not automatically evident where the queen came from if you read 'Qc5'. Especially if the piece didn't move for quite a while.

Originally posted by SwissGambit
In OP's situation, he would have had to look at the previous moves anyway - his opponent moved while he was away from the board.

Originally posted by tvochess
Hi Paul,

that's bad luck you had there. I play mostly online, so I can't know the feeling, but it must feel sour afterwards.

I think it's one of the downsides of short-hand algebraic notation. You only have a list of to-squares, not the from-squares. It's also hard to set-up a position from the middle- or endgame, because the notation doesn't provide ...[text shortened]... quick and simple win is Qf8#, right? :-), just joking. I'm actually thinking of Ra5, am I right?