Chess Opening Theory/1. e4/1...e6/2. d4/2...d5/3. Nc3/3...Bb4/4. e5/4...c5/5. a3/5...Bxc3/6. bxc3/6...Ne7/7. Qg4/7...O-O/8. Nf3/8...Nbc6/9. Bd3/9...f5/10. exf6

=French Defence, Winawer Variation= After White's 10. exf6 there is a threat of Qxg7 mate, and also the Ne7 is attacked. That's why the only reasonable response for Black is 10... Rxf6.

Theory table
'''1. e4 e6 2. d4 d5 3. Nc3 Bb4 4. e5 c5 5. a3 Bxc3+ 6. bxc3 Ne7 7. Qg4 O-O 8. Nf3 Nbc6 9. Bd3 f5 10. exf6'''