comment: A natural continuation of the previous move, although it's better to castle.
context: 1. d2d4  1... g8f6  2. c2c4  2... e7e6  3. b1c3  3... f8b4  4. d1c2 The Capablanca Variation against the Nimzo-Indian is solid and reliable, making it an especially good weapon if White only needs a draw. 4... d7d6  5. g1f3  5... b8d7  6. e2e3 A good way of developing. There are alternatives-White is usually slightly better. 6... b7b6  7. f1e2  7... c8b7  8. e1g1  8... b4c3 This move is necessary after White has castled, since the knight isn't pinned anymore and is ready to move, leaving the b4-bishop in danger. 9. c2c3  9... f6e4 Carlsen needed a win and embarks on a dangerous enterprise. 10. c3c2 