1. e2e4  1... e7e5  2. g1f3  2... g8f6  3. d2d4  3... f6e4  4. d4e5  4... d7d5  5. b1d2 A line that had a burst of popularity some 10 years ago, mainly thanks to the efforts of the  prominent Azerbaijani GM Vugar Gashimov. 5... e4d2  6. c1d2  6... f8e7  7. f1d3  7... c8g4  8. h2h3  8... g4h5  9. e1g1  9... b8d7  10. g2g4  10... h5g6  11. d3f5 White's key idea. Praggnanandhaa fixes his advantage  on the kingside and is patiently waiting for his opponent to castle there. 