The two young chess stars, both under 30, have one point each after drawing their opening two games of the tournament.
Italian prodigy Carlsen is seeking to cement his reputation as one of history's greatest chess players, while Caruana is another young star helping to return mass appeal to the highbrow game.
Chess has its own unique scoring system that awards the winner of each game one point, while a draw sees the contenders get half a point each.
The title goes to the first person to reach 6.5 points, with a rapid series of tiebreakers played in case the two are level after the first 12 games
They have an expected ten games left to play, scheduled until November 26.