X-Ray

How difficult?

Yesterday morning, I had this position in a blitz game. While looking for tactics exercises for my beginning students after showing them Paul Morphy's Opera Game, I put this position on the demo board. We did not discuss it, as they were busy playing chess and I was working with them on basic manners and sportsmanship.

After club, I put the position on Facebook thinking most followers there would solve it quickly. Although the second person to post offered the strongest move, which I had played in the game, I was surprised at some of the other responses. Is this position more difficult than I thought?

White to move

It seemed to me that it should be easy to remove both knights and then snatch the bishop.

15.e4

The strongest move, according to Stockfish.

I expected 15...Nb4 16.Bxf6 gxf6 17.Qxd7 and a clear advantage for White, probably decisive.

Black could have made things interesting with 15...h6, when the strange looking 16.Bh4 is the engine's choice. The computer likes 16...g5 17.Qd2

Black to move

Analysis position

I would have been stunned by 15...h6, realizing that my advantage was not to be gained as easily as initially anticipated, and played 16.Bxf6 Nxf6 17.e5 Nd5 and then would have considered 18.Bxd5.

Looking through this game this morning, I found that I used a mere two seconds on the position in the first diagram. My recollection of the game was that I had used more time than that. It turns out that I had spent twelve seconds on this position the previous move. I planned 15.e4 before exchanging my knight for my opponent's bishop.

White to move

14.Nxb6 Qxb6

Now, the position is the first diagram is reached. My opponent had played 13...Bd7, placing the bishop on a vulnerable square. Superficially, this error is a simple developing move that prepares to bring the bishop to a better square while connecting the rooks.

After my 15.e4, my opponent thought for thirteen seconds. As it was a three minute blitz game, that's a relatively long think.

15...Bc6

This move surprised me, but my reply was simple and easy.

16.exd5 Nxd5

White to move

17.Qg4

Again, I played the strongest move with fantasies of getting an easy checkmate or otherwise exploiting a pin along the g-file. Nonetheless, I spent fifteen seconds on this move.

17...f6 18.Bxd5

How did I miss 18.Qxe6+? Checkmate fantasies.

We played another fifteen moves before my opponent resigned.