I made a big mistake... but the computer liked my move!

I played an excellent game with black earlier today.

I got a big strategical edge after the opening, and the conclusion came quickly with a rook sacrifice which was a definite blow for my opponent, who soon resigned.

The computer analysis made me even happier: I had 0 inacurracies, 0 mistake and 0 blunder, only 7 apc loss overall.

A perfect game, for once? Not so fast.



When I looked at the lines after 20... Rxf4 (indeed the first computer move), I had a very bad surprise: the move I wanted to play then would have been a blunder. After he took my rook with 21. Rxf4, I was going to play Qxe3+ 22. Qxe3 Bxe3. Except that he has the simple 23. Rf2 and I have to fight for a draw in the endgame.

So why did the computer like my horrible idea? Because I can take with the bishop instead:
21... Bxe3+ and after 22. Rf2 I have a huge attack against his king, for example: 22... Qg5 23. Kf1 Bxf2 24. Kxf2 Rf8+ 25. Ke1 (only move that doesn't lose the Na4) Qxg4 and it's completely winning.

Actually, his best answer after 22... Qg5 is 23. Qf5 Bxf2+ 24. Kxf2 Qd2+ and I am much better in spite of the material: his king is exposed, his knight could soon fall. But it's still complicated.

The issue is I did not see any of this. And in case I had, I am not sure I would have correctly evaluated that.

The lesson is: I should have thought of the Rf2 move, and maybe played otherwise: after 20... Bd6 for instance, I still maintain the advantage.

Luckily for me, my opponent did not see Rf2 either, and instead of that he played an even more horrible move.

So, always check all the defensive options of your opponent before going for a sacrifice. Unless you want to have bad surprises.

Last but not least, it's possible to play a seemingly perfect game while making mistakes!

Have fun,

I don't think you have to actually see rook f2 to decide that bishop takes takes is better than queen takes. I guess I don't see the logic of wanting to trade queens there except wanting to trade all the pieces since you are up material. But I think your queen is better than his queen and his king is unsafe so why trade? I think that is the error is reasoning more than not seeing rook f2 since if you see it after bishop takes you are probably high rated enough to find queen g5.

This was the closest position I could make that got the rook out of that tactic. There's a FEN to put in.

kr6/pp2q2p/2p4R/2bp4/N5P1/3QP3/PP5P/R5K1 b - -

There, it evaluates bishop takes at -4 while queen takes is only -1.5 and that's where they both clearly win material. I think the trade as many pieces as possible mentality was the problem here.

Edit: r6k/pp2q1p1/2p4p/2bp4/N4RP1/3QPP2/PP5P/R5K1 b - - 0 1

That FEN is closer to the real position. Still -3.5 with bishop takes and -2 with queen takes.

I did not see it that way, I guess you have a point. To keep queens on the board would have been a good idea anyway.
But in blitz situations, I usually make practical choices. I think I prefer safety, and trading queens means we are playing for two results.

However, in the examples you show, Black end up with only one more pawn. In my game, the idea was that after 21. Rxf4 Qxe3+ 22. Qxe3 Bxe3 23. Kg2 Bxf4 I have two pawns more, so the endgame is totally winning (the computer says it's a +3 advantage).

So, I understand it's good to maximise you position, but sometimes we are lazy and go for the simpler (although not so strong) way.

PS: And finding Qg5 is not that easy, I mean the intuitive way of playing is to attack the Rf2, which is bad. So... I don't know.