The center deserves to be overprotected.
1. g1f3 Rapport needs only a win and, therefore, decides to avoid the classical theoretical lines on which his opponent has built his opening repertoire. 1... d7d5  2. g2g3  2... g8f6  3. f1g2  3... e7e6  4. e1g1  4... f8e7  5. d2d3  5... e8g8  6. b1d2 There is revived interest in the King's Indian Attack. 6... b8c6 Which, in turn, forces Black to search for new resources. The move in the game prepares e6-e5, effectively entering into a reversed Pirc. 7. d3d4 Rapport had already played like that in the past. He is trying to make use of the fact that c7-c5 is not possible at the moment. 7... f6e4 Black also makes use of the given opportunity. 8. c2c3  8... f7f5 And builds a Stonewall setup. It is amusing how often a pawn chain can be readapted in semi-closed openings. 9. f3e1 A typical pirouette in the Stonewall. Knight on the right frees the spot for its colleague while heading towards the d3-square in order to take the vital e5-point under a firm control. 9... e6e5 Not giving the square without a fight. 10. d2f3  10... e7f6  11. e2e3  11... b7b6 This is a novelty. So far both players have followed an earlier game of the Hungarian GM. 12. e1d3 Following his main plan.