Novak Djokovic said he was going to play this match as if it were the last of his career, that he was going to pour every ounce of his heart and soul into trying to do what few thought could ever be done again.
It was not enough.
With a startling display of power and creativity, Daniil Medvedev upset Djokovic, 6-4, 6-4, 6-4, in the final of the U.S. Open on Sunday, ending Djokovic’s bid to become the first man in 52 years to win all four Grand Slams in a calendar year. It was one last twist in a tournament that overflowed with stunning performances.