Aug. 4 (UPI) -- Track athletes earned most of Team USA's medals at the 2020 Summer Games on Wednesday in Tokyo. Japanese skateboarder Kokona Hiraki, 12, also made history on Day 12 as the youngest Olympic medalist in 85 years.
Team USA remains atop the medal count, with 79. China ranks second with 70, but leads the Games with 32 golds. The Americans' 31 second-place finishes are the most for second-place finishes.
Sydney McLaughlin brought in the first of six U.S. medals Wednesday when she clocked a world-record time of 51.46 seconds in the women's 400-meter hurdles. She finished just ahead of teammate Dalilah Muhammad, who won the silver.
Femke Bol of the Netherlands claimed bronze.
Team USA's Courtney Frerichs scored another medal in the next final. Frerichs claimed silver behind Uganda's Peruth Chemutai in the women's 3,000-meter steeplechase. Kenya's Hyvin Kiyeng earned bronze.
The Americans missed the podium in the men's hammer throw and 800-meter race, but claimed two spots in the men's 200-meter race, the final track event of the day.
Canada's Andre de Grasse won the event with a national-record time of 19.62 seconds. Americans Kenneth Bednarek and Noah Lyles earned silver and bronze, respectively. Team USA's Erriyon Knighton placed fourth.
In boxing, Team USA's Richard Torrez Jr. advanced out of his men's super heavyweight +91-kilogram semifinal. Torrez beat Kazakhstan's Kamshybek Kunkabayev.
Torrez will fight Uzbekistan's Bakhodir Jalolov in the men's super heavyweight +91-kilogram gold medal bout Sunday at Kokugikan Arena in Tokyo.
China's Gu Hong beat American Oshae Jones in a welterweight 64 to 69-kilogram boxing semifinal. Jones leaves the Olympics with a bronze medal.
In sailing, Team USA finished fourth in the men's two-person dinghy race. Australia won that event. Sweden and Spain earned respective silver and bronze medals.
In women's skateboarding, Team USA's Bryce Wettstein placed sixth in the park final. Japan's Sakura Yosozumi won that event.
Hiraki won silver to become the youngest Olympic medalist since Inge Sorensen of Denmark won bronze in the women's 200-meter breaststroke at the 1936 Summer Games.
Great Britain's Sky Brown won bronze in the park final. Brown, 13, is the Great Britain's youngest Summer Olympian of all time.
In non-medal events, Team USA beat the Dominican Republic in a men's baseball elimination game. First baseman Triston Casas went 1 for 3 with a two-run homer to lead the Americans into the semifinals.
Team USA battles South Korea on Thursday in Yokohama, Japan for a chance to play in the gold medal game.
In women's basketball, Team USA beat Australia 79-55 in a quarterfinal. WNBA star Breanna Stewart scored a game-high 23 points for the Americans.
Team USA battles Serbia on Friday for a trip to the title game.
In water polo, Spain beat Team USA 12-8 in a men's quarterfinal.
In golf, Madelene Sagstrom of Sweden fired a 5-under par 66 for a one-stroke lead in the first round of the women's tournament. Team USA's Nelly Korda and Aditi Ashok of India are tied for second place at 4-under par.
The tournament continues through Saturday at Kasumigaseki Country Club in Saitama, Japan.
Team USA's Brooke Raboutou also qualified for the women's sport climbing final. Sport climbing is one of four sports to debut at the 2020 Summer Games, along with skateboarding, surfing and karate.