2019 Rakuten Japan Open Tennis Championships

The 2019 Rakuten Japan Open Tennis Championships was a men's tennis tournament played on outdoor hard courts. It was the 46th edition of the Japan Open, and part of the ATP Tour 500 series of the 2019 ATP Tour. It was held at the Ariake Coliseum in Tokyo, Japan, from September 30 through October 6, 2019. First-seeded Novak Djokovic won the singles title.

Seeds

 * 1 Rankings are as of September 23, 2019.

Other entrants
The following players received wildcards into the singles main draw:
 * 🇯🇵 Taro Daniel
 * 🇯🇵 Go Soeda
 * 🇯🇵 Yūichi Sugita

The following player received entry as a special exempt:
 * Lloyd Harris

The following players received entry from the qualifying draw:
 * 🇪🇸 Pablo Andújar
 * 🇦🇺 John Millman
 * 🇦🇺 Alexei Popyrin
 * 🇯🇵 Yasutaka Uchiyama

Withdrawals

 * Before the tournament
 * Kevin Anderson → replaced by 🇮🇹 Lorenzo Sonego
 * 🇷🇸 Laslo Đere → replaced by 🇦🇷 Juan Ignacio Londero
 * 🇫🇷 Pierre-Hugues Herbert → replaced by 🇦🇺 Jordan Thompson
 * 🇯🇵 Kei Nishikori → replaced by 🇷🇸 Miomir Kecmanović
 * 🇨🇦 Milos Raonic → replaced by 🇯🇵 Yoshihito Nishioka
 * Stan Wawrinka → replaced by 🇷🇸 Filip Krajinović

Seeds

 * Rankings are as of September 23, 2019.

Other entrants
The following pairs received wildcards into the doubles main draw:
 * 🇬🇧 Luke Bambridge / 🇯🇵 Ben McLachlan
 * 🇫🇷 Fabrice Martin / 🇯🇵 Yasutaka Uchiyama

The following pair received entry from the qualifying draw:
 * 🇮🇳 Divij Sharan / 🇳🇿 Artem Sitak

Singles

 * 🇷🇸 Novak Djokovic defeated 🇦🇺 John Millman 6–3, 6–2

Doubles

 * 🇫🇷 Nicolas Mahut / 🇫🇷 Édouard Roger-Vasselin defeated Nikola Mektić /  Franko Škugor, 7–6(9–7), 6–4