Bluff in chess - refuting opponent’s opening play

When your opponent is playing the opening of a chess game almost without thinking, it is hard to imagine that he is making severe blunders and that his play should be refuted. Most likely everything had been checked on a computer and has been played before either by him, or by other players in the database. But here is an example where my opponent “was just playing too fast”. I think after playing 2 games a day for 4 days in a row, he simply did not want to spend too long on this last round game.

Jiganchine – McLaren, BC Championship, 2008

White to move. Find the most promising continuation.s

Black has been playing very fast so far in this tournament game, and even though I was pleased with having a centralized knight on e4, I did not look too far for a tactical refutation as well. Yet after 17. Nd6! Qc7 (I was incorrectly concerned about 17… e4, but that is just wasting time since the knight wants to come to g5 anyway) 18. Nfg5 Nd8 Qe1!? – Black’s position has too many weaknesses, and White is going to win at least a pawn – Black can’t guard the e5 pawn, while also trying to cover up f7. Black’s pieces are also too passive to provide any real compensation for it.

Black to move. White is practically winning

Instead I wanted to keep a positional advantage and blockade on e4, and lost all of my advantage after 17 Nfg5? Nxe4 18. Nxe4 f3! with unclear position. The game ended well for me, but this was definitely a mistake on my part early out of the opening. Had my opponent been making his moves a bit slower, I would actually try to play more aggressively. Instead, I wanted to play solid moves and just blockade e4,which gave me nothing special. So in that sense, his “bluff” actually worked quite well for him! I go over the entire game in this video.