#1 Novak Djokovic
After the disastrous first half of the season he had, no one would have predicted Novak Djokovic to even qualify for the World Tour Finals.
He was upset by Hyeon Chung at the 4th round of the Australian Open and by Marco Cechinato at the quarters of the French Open and was shocked by many other lower ranked players in the first half of the year.
However, his season turned around when the grass season began. He reached the final of Queens Club and then went on to win the third Wimbledon title of his career, defeating Kevin Anderson in the final, not before beating Nadal in the semis in a match which lasted for over five hours.
Shortly after Wimbledon, he achieved the Career Golden Masters when he won the Cincinnati Open, defeating Federer in the final. He went on to win the US Open as well and the Shanghai Masters which followed. He reached the final of the Paris Masters and the Tour Finals as well but fell to two youngsters in the form of Karen Khachanov and Alexander Zverev respectively.
He ends the year as the world no. 1.
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