1. e2e4  1... c7c5  2. g1f3  2... d7d6 Duda is not afraid to enter the sharp Sicilian lines. 3. f1b5 Whereas Carlsen prefers a more positional approach. 3... c8d7  4. b5d7  4... d8d7  5. e1g1  5... g8f6  6. d1e2  6... b8c6  7. c2c3  7... e7e6 