Kerr said the decision was made out of an abundance of caution as the Warriors go through a condensed training camp.
"Just feel more comfortable giving him a little more of a ramp up," Kerr said ahead of the Warriors' 96-87 win over the Washington Wizards on Friday. "He's just not quite ready to play at this point just based on where, you know, we're so early in camp. We just want to be safe and make sure he gets a good ramp up before he plays in games."
The Warriors held just three practices in San Francisco before boarding the 11-hour flight to Japan last Wednesday.
"Just coming off the two years with the injuries, this is really unique to play a game after 3½ practices so we're just being cautious and trying to do the smart thing," Kerr said.
Thompson was under a strict game restriction last season -- starting under a minute restriction and never playing in back-to-back games -- after missing two consecutive seasons with leg injuries.
After the Warriors return to the Bay Area, they will have one full week before their next preseason game.