New Delhi/Bengaluru, April 26 -- Fabiano Caruana and Ian Nepomniachtchi sat, spent and disconsolate. Neither had lost the game, but both had lost their chance. "I'm very, very sorry," Nepomniachtchi said to his opponent. Fabiano replied, "My fault," and rose from his chair with a crack of a self-pitying smile. Their drawn final-round game, which yo-yoed between opportunity and blunder, decided the fate of the Candidates tournament and ushered in a historic teen champion....