Petrov's Defense: Modern Attack
C43 1. e4 e5 2. Nf3 Nf6 3. d4 exd4
Black scores 46.3% here across 576 club games — but the 8.0% who answer d6 score 32.6%, 14 points worse.
What Black actually plays here
Across 576 games from a Lichess-derived book of club play, Black scores 46.3% in this position. These are the replies people choose, and how each one works out.
| Reply | Games | Share | Black scores | Verdict |
|---|---|---|---|---|
| exd4 | 232 | 40.3% | 50.9% | holds up |
| Nxe4 | 192 | 33.3% | 44.5% | holds up |
| Nc6 | 57 | 9.9% | 51.8% | holds up |
| d6 | 46 | 8.0% | 32.6% | below the line |
| d5 | 35 | 6.1% | 41.4% | below the line |
"Below the line" means the reply scores at least three points worse than the position does overall. Replies played fewer than 25 times are left out: the sample is too small to read.
Is this costing you anything?
A table of averages cannot tell you whether you go wrong here — only your own games can. Opening Leak Lab reads your Chess.com or Lichess archive, finds the decisions you repeat, and checks each one against this book and a bundled Stockfish.