The Dangers of Playing well

I want to share a game I recently played in the Lichess4545 league. The reason for sharing this game isn't that it's really great, but that I made a big psychological and very common mistake: I got way too confident.

Before the game, I saw that my opponent played the Alekhine defence against 1.e4 and so I prepared quite a bit for the game. In fact, I saw that they had reached the game position after white's 15th move twice before, both times making the blunder 15...Nxd4??

Knowing that and seeing that the game was steering quickly into the right direction, I thought that it might be quite likely that they make the same mistake again. This game, they played something different (and better), but I still knew that my position was clearly better according to the engine and I soon started looking for forced ways to reach a clear and big advantage which was the beginning of my big mistake.

1.e4 Nf6 2.e5 Nd5 3.d4 d6 4.c4 Nb6 5.f4 dxe5 6.fxe5 Nc6 7.Be3 Bf5 8.Nc3 e6 9.Nf3 Be7 10.Be2 O-O 11.O-O f6 12.exf6 Bxf6 13.Qd2 Qe7 14.Rad1 Rad8 15.Kh1 Bg6 16.Qc1 Rd7

17.Bg5?

This was my fist big psychological mistake of the game: up to move 15, everything was preparation and I knew that black's natural plan of doubling rooks on the d-file wasn't one of the top engine lines. So I assumed that there had to be some concrete refutation and tried to prove that I had a win instead of looking for resources for my opponent.

17...Bxg5 18.Qxg5 Qxg5??

18...Rxf3! -+ Removing the defender of the queen

19.Nxg5 Rxf1+ 20.Bxf1 Nxd4?! 21.c5!

I had calculated this far and seen this resource before playing 17.Bg5.This was another sign for me that I was playing really well.

21...Bh5 22.Rd3?!

Another move that made me feel very clever since I really liked the idea of sacrificing the exchange on d3 rather than on d1.Again, I didn't look at my opponent's resources

22...Bg6?

Somehow my opponent was under the same faulty impression as me

22...Nc4 23.Nxe6?? This was my intended resource: with the white rook on d1, white would be winning 23...Rf7 -+ Exploiting the weakened back rank

23.cxb6! Bxd3 24.bxa7 Rd8 25.Bxd3

This was the point of sacrificing the exchange on d3 and not on d1: instead of having to retreat with the knight to d1 in order to recapture the bishop, I can develop my own bishop.

25...h6 26.Bh7+?!

Missing that my bishop will possibly get into trouble on h7

26...Kf8 27.Nb5

Again I have seen this move before playing 26.Bh7+ and thought that it had to be right and didn't look at many alternatives for my opponent

27...hxg5?

27...Ke7! 28.Nxd4 Rxd4 29.Bc2 White has to defend the back rank 29...Rd8 30.Ne4 White is still better with two minor pieces for the rook but not clearly winning

28.Nxc7 Kf7

29.a8=Q?

Here I was just waiting for black to resign and only realised later that my bishop will get stuck on h7

29.Bd3! Saving the bishop and preventing a back rank mate after the knight moves

29...Rxa8 30.Nxa8 g6 31.Nc7 Kg7 32.b4

Another move that strengthened my ego: instead of taking a pawn on g6, I decided to push my pawns and force the king to a worse square

32...Kxh7 33.a4 Kg7 34.b5 Nb3 35.Nxe6+?

This throws away white's advantage

35...Kf6 36.Nd8

Blundering the second piece. I didn't see 36...Na5 since I was still so pleased with myself

36...Na5! 37.Kg1 Ke7 38.Nxb7 Nxb7

The miraculous thing about this game is that white doesn't lose after blundering two pieces.

39.Kf2 Kf6 40.Ke3 Ke5 41.Kf3 Kf5 42.Ke3 Ke5 43.Kf3 Kf5 44.Ke3 Ke5

1/2-1/2

1. Don't rely too much on the engine evaluation after the opening. Even though the engine said that the position is around +1 for white as I got out of book, there is still a whole game left to be played and with many pieces on the board, +1 doesn't mean that the win is easy.
2. Don't think about how great you are playing. As soon as you start having thoughts about how well (or also how poorly) you are playing, you take your attention away from the game. When playing well, this can also break your flow and you will think about the result and showing the game to other people instead of thinking of the best moves.
3. Focus on looking wide instead of deep. One reason why I felt like I was playing amazingly is that I calculated some lines very deeply. But this came at the cost that I didn't look at many options and therefore I missed A LOT of things during the game. Calculating short lines accurately is much better then miscalculating long lines.