The score became 3.5: 2.5 in favor of the Norwegian chess player.
The Russian played with black pieces.
The previous five games for the world chess crown ended in a draw.
The match consists of 14 classical chess games.
The match for the world chess crown is taking place in the UAE and will end on December 16.
Earlier, Nepomniachtchi's coach said that the results of the debut were in Ian's favor, Carlsen was uncomfortable.