The bishop on d2, waiting
1.e4 d5 2.exd5 Qxd5 3.Nc3 Qa5 4.d4 Nf6 5.Nf3 Bg4 6.Bd2 e6 7.Nd5
- The mistake
- Developing while the queen on a5 sits on a diagonal with a white bishop at the end of it.
- Why it costs
- 6.Bd2 looks like a modest developing move. It is loading a discovered attack: 7.Nd5 steps the knight out of the way, so the bishop hits the queen while the knight itself forks c7 and f6. Black comes out of it a piece or the exchange down, or with a king that cannot castle.
- Instead
- Play …c6 early. It gives the queen b6 and c7, blunts the diagonal and supports …d5 ideas later — which is why it comes before almost anything else in this opening.