During the first day of the play at the Japan Open in Tokyo, five matches were played in which home tennis players pleased the spectators, only Sugita, who lost to Cilic did not go through into the next round.
In the first match, home player Go Soeda who sits on the 133rd place in the ATP ranking and got a wild card in the tournament created first surprise of the tournament. The Japanese surprised Jan-Lennard Struff, who won the first set and had a break ball in the second, but couldn't use it.
Fans in Tokyo also enjoyed the victory of Yoshihita Nishioka, who coped with Joao Sousa 7-5 and 6-3. Yuchi Sugita lost to Marin Cilic 6-4 and 6-4.
Other players who advanced were Lucas Pouille and Hyeon Chung, who turned the match with Sonego.
First day results at the Japan Open:
| | | Struff J-L. (Ger) | 1 | 6 | 64 | 3 | | | | | |
| Soeda G. (Jpn) | 2 | 4 | 77 | 6 | | | |
|
| | | Hurkacz H. (Pol) | 0 | 4 | 3 | | | | | | |
| Pouille L. (Fra) | 2 | 6 | 6 | | | | |
|
| | | Sugita Y. (Jpn) | 0 | 4 | 4 | | | | | | |
| Cilic M. (Cro) | 2 | 6 | 6 | | | | |
|
| | | Nishioka Y. (Jpn) | 2 | 7 | 6 | | | | | | |
| Sousa J. (Por) | 0 | 5 | 3 | | | | |
|
| | | Sonego L. (Ita) | 1 | 6 | 3 | 4 | | | | | |
| Chung H. (Kor) | 2 | 3 | 6 | 6 | | | |