Swimmer Naohide Yamaguchi won gold in the the men's SB14 100-meter breaststroke on Sunday to give the host nation a second Paralympic title in the pool.
Yamaguchi improved on his own world record with a time of 1 minute, 3.77 seconds to beat Australian Jake Michel by 0.51 seconds. Scott Quin of Britain won bronze.
Yamaguchi is a world champion in the event. This is the 20-year-old's first gold at the Paralympic Games.
Before winning gold on Sunday, Yamaguchi had finished fourth in both the men's S14 100 butterfly and in the 4x100 freestyle relay. In the former, he missed a medal by just 0.21 seconds.
The gold is the host nation's third of the Tokyo Games. Takayuki Suzuki won Japan's other swimming gold in the men's S4 100-meter freestyle.