1. g1f3  1... g8f6  2. c2c4  2... e7e6  3. d2d4  3... d7d5  4. b1c3 The players reached a popular Queen's Gambit tabiya by a less common move order. The Mongolian first board opts for the Ragozin Defense out of many reasonable possibilities. 4... f8b4  5. c1g5  5... h7h6  6. g5h4 A clever choice by Carlsen. It was safe to assume that his young opponent was booked up in the main lines after 6.Bxf6 Qxf6, so the Norwegian deviates early. With this move, he tries to steer the game into less explored territories. 6... e8g8 Judging by the time spent on this move, it seems Batsuren was surprised by the world champion's move and decided to play it safe instead of going for the critical continuation. 7. e2e3  7... b8d7 Black continues developing in a relatively passive fashion. 8. c4d5 This is a good moment to make this exchange for two reasons: (1) White doesn't want to lose a tempo developing his light-squared bishop to d3, so he eliminates the dxc4 possibility. (2) Having put his knight on d7, Black has blunted the c8-h3 diagonal for his light-squared bishop, so we don't have to worry about moves like ...Bg4 anymore. 8... e6d5  9. f1d3  9... c7c6 Black is going for the classical QGD setup with the Carlsbad structure, although that means his bishop on b4 is misplaced. 10. e1g1  10... b4d6 