The win ensures Samurai Japan will win its first Olympic medal in baseball since the 2004 Athens Games.
Defending champion Inbee Park is three strokes back, while Japan's Nasa Hataoka is tied for 16th.
The Japanese teenager has come into his own at the Tokyo Games, earning three medals.
Ryoji Kuribayashi holds the U.S. in the 10th to pick up the win.
Kazuma Kaya captures the bronze medal in the men’s pommel horse.
Masters champion Matsuyama stayed in contention but missed clutch putts down the stretch.
Kenyans look to be the favorites, but Japanese runners are hoping for a surprise in Hokkaido.
Hideki Matsuyama is one stroke off the pace entering the final round of the men’s golf tournament at Kasumigaseki Country Club.
Japan will face the U.S. on Monday for a chance to reach the semifinals.
Unheralded Austrian Sepp Straka takes the early lead with an Olympic-record 63 at Kasumigaseki Country Club.
Sakamoto's sayonara single caps a dramatic comeback as the hosts win the first game of the baseball tournament.
Takanori Nagase won the under-81-kg division title in judo, becoming the first Japanese to do so since Makoto Takimoto at the 2000 Sydney Games.