The Winning Academy 19: Typical Mistakes when Analysing with an Engine

by Jan Markos
7/3/2023 – They are so much better than us. They solve the most complicated positions in seconds.And they are so available. Anyone can buy them and use them at home. And frankly, we all use them. Chess engines. These artificial beasts are very useful when used wisely. But frankly, most club players tend to rely on them too much and use them mindlessly. In the following article I would like to show you three typical mistakes you should avoid when using a chess engine. And to show that even the best sometimes fail to tame the engines, I have chosen the examples from games played by Magnus Carlsen and his super-GM opponents. | Graphic: Europe Echecs

Middlegame Secrets Vol.1 + Vol.2 Middlegame Secrets Vol.1 + Vol.2

Let us learn together how to find the best spot for the queen in the early middlegame, how to navigate this piece around the board, how to time the queen attack, how to decide whether to exchange it or not, and much more!


When preparing an opening novelty with the help of an engine, you should always remember that your unprepared opponent will analyse his position with his own brain and will therefore prefer solutions that are natural for a human being, not for a silicon monster.

Therefore, always check the ideas that are natural to a human player, even if they are not among the first lines of your engine. If you do not, you will be caught off guard and surprised by your own novelty.

A typical example:

Carlsen-Giri, Carlsen Invitational 2020

For this rapid game, the World Champion had prepared a smart and complex novelty 13.Rg1!?, offering a piece sacrifice. Of course, Carlsen anticipated and analysed the direct 13…f4, and assumed that after 14.gxf4 gxf4 15.Bxf4 Bxf4 16.e3 Qe7 17.Qh5+ Kd8 18.Qxd5+ Bd6 19.c4 White has got good chances.

However, Giri was too smart to fall directly into a forcing line that his opponent checked at home with his engines. He played the normal 13…0-0. And he was surprised that Carlsen did not respond at once.

In his notes, Giri comments: “After this extremely natural move Magnus sank into thought. It is an unavoidable consequence of preparing with the computer that sometimes the most natural moves, if not entering the engine tab, are dismissed.”

And I think he is right. This is exactly what happened to Carlsen. After all, my engine does not list the castling among top 10 moves either, preferring various strange looking alternatives. However, the differences in evaluation are rather small, 13…0-0 is definitely not a bad move.

Although the World Champion reacted correctly with 14.h4, his psychological advantage was gone. Black won later after an interesting fight.

Here's the complete game:

A second typical mistake in opening preparation is to choose a line solely on the basis of the computer's evaluation. However, YOU will be playing the line at the board, not the computer. YOU will be the one making difficult decisions under pressure. Therefore, the question of whether YOU like the position and can handle it is just as important as the objective and abstract computer evaluation.

In the 2018 World Championship match, Caruana repeatedly tried to get an advantage against Carlsen in the 7.Nd5 line of the Sveshnikov Sicilian. The following pawn structure arose in several games of the match:

Caruana-Carlsen, World Championship match 2018, game 10, White to move:

Carlsen´s second Peter Heine Nielsen commented on this line: “While the engines indeed seem to give a preference for White, people tend to underestimate the human factor and that Black's position is easier to play, as he generally tries to aim for the opponent's king, while White has to balance positional gains on the queenside with also caring about the security of his own king.”

To put it shortly: for computers, the 7.Nd5 line is attractive and promising. For us mortals, it is extremely difficult to handle. Both was confirmed later in the game. After Black’s 23rd move, the following position arose:

Objectively, Caruana is winning. Any engine would take 24.Bxb5!, then find a couple of precise defensive moves and finally push the a-pawn, thus gaining a decisive material advantage.

For a mere mortal, however, it is extremely difficult to choose a move that deprives your king of an important defender. And in a World Championship match it is even more difficult. The danger of being mated in a few moves (and losing a game with the white pieces) is all too real.

Therefore, Caruana decide to pick a relatively safe option and played 24.g3. The game ended later in a draw.

Here's the complete game:

Thirdly, I would like to draw your attention to a typical mistake you can make when analysing your own games with an engine. Do not blindly follow the advice of your engine when it comes to identifying the critical moment or the crucial mistake! Why not? Let me explain with a simple example.

In the World Blitz Championship 2022, Carlsen desperately needed to win against a much lower-rated opponent, Madaminov. However, he failed to gain any advantage after the middlegame and was forced into a relatively easy and completely equal endgame with only 10 seconds on the clock. (Madaminov had over a minute left. After each move both players received a 2-second increment).

Carlsen-Madaminov, World Blitz 2022, White to move:

Still, the World Champion won in his trademark, seemingly effortless manner. Where did Madaminov actually go wrong? Please, have a look at the live video of the endgame here before continuing reading.

According to my engine, the critical position arose after Carlsen's 52.Kd3:

Madaminov played 52…Bc4+? and was lost after 53.Ke4 Kd6 54.Kd4. However, the ChessBase Let´s Check function claims that the diagrammed position is still drawn after 52…Bd5! 53.f4 Bc4+ 54.Ke4 Kd6 55.Kd4 Ke6!, attacking the f4-pawn. (The best engines in the world need depth over 40 ply to be sure.)

So should we assume that Mamadinov's decisive mistake was his 52nd move? Well, in an abstract, scientific sense yes.

However, from a practical point of view it makes little sense to assume that 52...Bc4+ was a crucial mistake. In a blitz game it is virtually impossible to see all the subtleties of the position and make all the precise, machine-like moves.

In fact, Madaminov's mistake was to get into such a dangerous position from a relatively safe endgame. So where did he go wrong? Well, as any good coach would easily see, he made a very dubious decision after Carlsen's 46.Kc3:

Black can play almost any move with his bishop. However, Madaminov played 46…a4?, putting another pawn on a light square, making it more vulnerable and creating a hole on b4.

The machine assumes that the position after 46…a4 is still equal, and therefore this move is as good as any bishop move. But it does not tell you that the path to equality is now much narrower than it would be with the pawn on a5.

Therefore, 46…a4 is a mistake despite the engine disagrees.

Similarly, an experienced GM might argue that Madaminov committed a mistake even earlier. Let’s have a look at the position after Carlsen’s 41.hxg5:

Madaminov played 41…Kf8?!. However, 41…f6! leads to a very simple draw, as after 42.f4 fxg5 43.fxg5 Bf5 White has a weakness on g5 and this fact severely limits the activity on his king. In the game, Carlsen transferred his king all the way to c3. That would never be possible with such a weak pawn on g5. In addition, after 41…f6! a pair of pawns gets off the board, which brings Black closer to trivially drawn endgames.

Again, any engine would claim that 41…Kf8?! and 41…f6! are of equal value. However, they are all wrong. The position after 41…f6 is much easier to manage in a blitz game.

Here's the complete game:


Fire is a good servant but a bad master, it is said. Engines are the same. If you follow their advice blindly, they may become a hindrance to your chess growth. But if you use them wisely enough, they will be of great help to you.

The role of a good coach or a more experienced chess buddy therefore remains vital. Not because people play better chess. We simply understand better what it actually means to be human.

Middlegame Secrets Vol.1 + Vol.2

Let us learn together how to find the best spot for the queen in the early middlegame, how to navigate this piece around the board, how to time the queen attack, how to decide whether to exchange it or not, and much more!


Jan Markos is a Slovakian chess author, trainer, and grandmaster. His book Under the Surface was the English Chess Federation´s 2018 Book of the Year. His last book, The Secret Ingredient, co-authored with David Navara, focuses on the practical aspects of play, e.g. time-management over the board, how to prepare against a specific opponent, or how to use chess engines during the training process. Markos was the U16 European Champion twenty years ago. At present he helps his pupils from several countries to achieve similar successes. Apart from focusing on the royal game, he is also the author of several non-chess books, focused on critical thinking, moral dilemmas, and phenomenology.