Protecting the pawn chain.
1. e2e4  1... e7e5  2. g1f3  2... b8c6  3. f1c4  3... f8c5  4. a2a4 In the open sea that is the theory of the Italian Opening, this move is a breath of fresh air, albeit a small one, since the positions are so similar that only those who have studied dozens of hours can begin to understand the subtle differences. In my database, this is only the 13th most popular move. To give you an idea, even 4.Bxf7+ has more games played (although I didn't check for double games or games played on blitz; that would be too much). 4... g8f6  5. d2d3 As I wrote before, 4.a4 is a very small breath of fresh air. After 5.d3 we're back to hundreds of games, although this is better than the customary thousands. To be fair, many transpositions are still possible. 5... d7d6  6. a4a5 Following the principle, Whoever says A must say B. Or, paraphrasing it: If you play a4, you must play a5. 6... c5b4 The position is finally gaining independent value. 7. c1d2  7... b4d2  8. b1d2  8... e8g8  9. e1g1  9... c6e7 The thematic maneuver is new in this position. 10. c2c3  10... e7g6  11. f1e1  11... h7h6 Gukesh is preparing Nh7-g5, exchanging a pair of knights. The computer suggests another plan: 12. d3d4  12... f6h7  13. e1e3 A good move, since the rook is useful on the third rank. There are options of equal value, the position of a \"slow\" character, meaning that many plans are possible. 13... h7g5  14. f3g5  14... d8g5  15. g2g3 Restricting Black's knight. 15... c8g4 This is inaccurate due to White's surprising reply. Black can keep only a small disadvantage, normal in opening play, with many moves. 16. h2h4 Black now must place the queen in a dangerous square or go to a worse endgame. 16... g5h5 The best decision. 17. d1b3  17... a8b8  18. d2f1 Preparing Nh2 and then Be2. Black's queen is in danger. 18... g6e7 Releasing the g6-square for the queen. 19. f1h2  19... g4d7  20. c4e2 Black's pieces are forced back; everything starts to go wrong. 20... h5g6  21. d4e5  21... d6e5  22. a1d1  22... d7e6  23. b3b5 The black queen remains poorly placed, a contrast to the activity of the white queen. 23... e7c6  24. a5a6  24... e6c8  25. h4h5  25... g6f6  26. e3f3  26... f6e6  27. e2c4  27... e6e7  28. b5a4 This move doesn't make a good impression. The queen was very well-placed on b5; it's a pity to move it back. 28... c6d8  29. a6b7  29... c8b7 Despite the weakened pawn structure, Black's position isn't so horrible anymore. 30. f3e3  30... b7c6  31. a4a2  31... d8b7 The knight returns to the game. 32. b2b4  32... b7d6  33. c4d5  33... c6d5  34. d1d5 The position remains unpleasant, but Black can defend with careful play. 34... e7e6  35. e3e2  35... c7c6  36. d5a5  36... e6a2  37. a5a2  37... f8c8 Preparing c6-c5, after which the draw is close. 38. h2g4  38... c6c5  39. b4c5  39... c8c5  40. a2a7  40... c5c3  41. a7d7 A very good practical attempt. 41... d6e8 After this move, the position again becomes quite difficult to defend. 42. g4e5  42... e8f6  43. d7e7  43... b8b4  44. g3g4 Defending the pawn on h5 and creating mating threats. 44... c3c5 Taking on e4 loses immediately: