"It's disappointing for me; I was in the driver's seat for a set and a half and had a break, but I have to give him huge credit," said world No. 1.
Will Smith stars as iconic tennis coach and father Richard Williams in new biopic.
The ITF has moved Thursday's matches to a 3 p.m. start time.
Two-time gold-medal champion and partner Joe Salisbury suffer heart-breaking loss.
The heat was oppressive on Wednesday at Tokyo, and players were suffering.
Simone Biles said she was inspired by Naomi Osaka putting mental health first in pulling out of gymnastics team final.
Nine current Top-20 singles players are playing mixed in Tokyo.
