Chess Opening Theory/1. e4/1...e5/2. Nf3/2...Nc6/3. Bc4/3...Nf6/4. Ng5/4...d5/5. exd5/5...Na5/6. Bb5/6...c6/7. dxc6/7...bxc6/8. Qf3/8...Rb8/9. Bd3/9...h6

= Two Knights:Colman's Defence =

9...h6
The theory move for years, given an exclamation mark by Estrin although quite why is unclear. The White Knight is now forced to make a good move to the e4 square.

Theory table
.
 * 1.e4 e5 2.Nf3 Nc6 3.Bc4 Nf6 4.Ng5 d5 5.exd5 Na5 6.Bb5+ c6 7. dxc6 bxc6 8. Qf3 Rb8 9.Bd3 h6

Statistics
Estimated next move likelihood Ne4 100%