As Friday 3 December ticked over into Saturday morning in Dubai, Magnus Carlsen edged ahead with the sixth game of his title defence against Ian Nepomniachtchi. After five draws, Carlsen broke the deadlock by winning the longest game in World Chess Championship history: nearly eight hours of play and more than 130 moves each. The extremely high levels of play from both players in the first week of the contest promised well for the second half of the fourteen-game match. But less than a week later it was all over: Nepomniachtchi contrived to lose three of the next five games, and Carlsen was declared the champion for the fifth time on Friday 10 December.