the ATP Finals. At the ATP Finals, Nishikori was seeded seventh. He was drawn in Group Lleyton Hewitt and faced second seed Roger Federer in his first match, defeating him in straight sets. This was Nishikori's first victory over Federer since 2014 and ended a six-match losing streak against him. He was eliminated in the group stage after losing his next two matches against Kevin Anderson and Dominic Thiem. He ended the season ranked World No. 9. 2019: First title since 2016 Nishikori started his 2019 season at the Brisbane International, where he was seeded second. He defeated Denis Kudla, sixth seed Grigor Dimitrov, and Jérémy Chardy to reach the final, where he defeated fourth seed Daniil Medvedev in three sets to win the title. This was his first tournament victory since February 2016 and broke his streak of nine consecutive final losses. At the Australian Open, Nishikori was seeded eighth. In the first round, he faced qualifier Kamil Majchrzak, who was making his Grand Slam main draw debut. Majchrzak took the first two sets in just 90 minutes, before suffering from cramps. Nishikori won 15 of the next 17 games, before Majchrzak retired down 3 games to none in the fifth set. In the second round, he faced Ivo Karlovic, against whom he took the first two sets before dropping the third and fourth. The fifth set proceeded to a tiebreak, which Nishikori won 10–7. In the fourth round, he faced 23rd seed Pablo Carreño Busta. He dropped the first two sets before staging a major comeback, winning the third and fourth and leading by a break in the fifth before failing to serve out the match. Nishikori narrowly forced a tiebreak, trailing until a crucial point at 8–5, in which Busta contested an incorrect late call. The umpire awarded the point to Nishikori, who proceeded to win the tiebreak 10–8. He thus advanced to his fourth Australian Open quarterfinal, where he retired in the second set against Novak Djokovic. At Rotterdam, Nishikori was the top seed. He defeated Pierre-Hugues Herbert, Ernests Gulbis and Márton Fucsovics before he lost in the semifinals to Stan Wawrinka. At Dubai, he entered as first seed, defeating Benoît Paire in the first round before being upset by Hubert Hurkacz. At Indian Wells, he was the sixth seed in the singles draw, defeating Adrian Mannarino before losing again to Hubert Hurkacz. He also entered