July 27 (UPI) -- Gymnasts, swimmers, a triathlete and a surfer were among those who won Team USA's 11 medals Tuesday at the 2020 Summer Games. The performances helped the Americans take over as medal count leaders through Day 4.
The Americans started the day four medals behind China for the overall lead. Team USA then captured two gold, five silver and four bronze medals in Tuesday's events.
Team USA pushed its four-day total to 25 medals. China has the second most at 21. Japan and the Russian Olympic Committee are tied for third with 18.
The day's medal run ended in drama for the Americans at Tokyo's Ariake Gymnastics Center. Team USA won a silver medal in the women's gymnastics team final, but could complete without star gymnast Simone Biles during the rest of the events.
Biles withdrew from the competition after her first rotation on the vault and said she is "day-to-day" to return. She is not injured, but cited "stress" from the Games as the reason for her early exit.
"No injuries, that's why I took a step back," Biles told reporters. "I didn't want to do something silly and get injured. I thought it was best if I there girls took over and did the rest of the job, which they absolutely did."
Grace McCallum, Jordan Chiles and Sunisa Lee completed the competition and posted the second-best score, behind the gold medal squad from the Russian Olympic Committee. Great Britain won bronze in the women's team final.
Lee tied Belgium's Nina Derwael for the highest overall score on bars, with a 15.400. She totaled the second-highest score on on the balance beam. Chiles posted the third-highest score on vault.
Triathlete Katie Zaferes won the first medal for Team USA on Day 4. She claimed bronze with a time of 1:57:03 in the women's individual race. Bermuda's Flora Duffy won the women's triathlon. Great Britain's Georgia Taylor-Brown placed second.
Carissa Moore later won the first gold medal for surfing in Team USA history -- in Chiba, Japan. She beat South Africa's Bianca Buitendag in the gold medal match at Tsurigasaki Surfing Beach.
Swimmer Regan Smith won the first medal for swimming on Day 4. She placed third in the women's 100-meter backstroke. Australia's Kaylee McKeown won that event, followed by Canada's Kylie Masse.
Ryan Murphy won another bronze in the next swimming event. He finished third behind Russian Olympic Committee duo Evgeny Rylov and Kliment Kolesnikov in the men's 100-meter backstroke.
Lydia Jacoby, 17, won Team USA's first gold medal of the day in the women's 100-meter breaststroke swimming final. South Africa's Tatjana Schoenmaker won silver. Team USA's Lilly King finished third for bronze.
Team USA also claimed silver medal in the women's synchronized 10-meter platform diving final. China and Mexico won gold and silver, respectively.
Later Tuesday, Japan beat Team USA 2-0 the gold medal softball game. Canada beat Mexico 3-2 in Tuesday's bronze medal game.
Team USA added another silver medal to its Summer Games total with a second-place finish in the equestrian dressage team grand prix special. Germany won that event. Great Britain claimed a bronze medal.
Mary Carolynn Tucker and Lucas Kozeniesky led Team USA to a silver medal in the 10-meter air rifle mixed team final. China won gold and the Russian Olympic Committee won bronze in that event.
In non-medal events, the United States Women's National Team secured a spot in the knockout rounds of soccer tournament with a 0-0 draw with Australia. The Americans face the Netherlands in the quarterfinals Friday in Yokohama, Japan.
Team USA's women's basketball team beat Nigeria 81-72 in the preliminary round. A'Ja Wilson led Team USA with a game-high 19 points and 13 rebounds. Brittney Griner chipped in 13 points and 10 rebounds in the victory.
Team USA's April Ross and Alix Klineman beat Spain's Liliana Fernandez Steiner and Elsa Baquerizo McMillan 2-0 in the preliminary round of the women's beach volleyball tournament.
Americans Philip Dalhausser and Nicholas Lucena beat Brazilians Alison Cerutti and Alvaro Morais Filho in their men's preliminary match.
Japan beat Team USA in pool play in the women's 3x3 basketball tournament. Team USA faces France on Wednesday in a semifinal game to determine who meets in the women's 3x3 basketball gold and bronze medal games.
The Olympic swimming competition resumes Wednesday in Tokyo and airs starting at 9:30 p.m. EDT Tuesday on NBC.
Team USA's nine gold medals overall are tied with China for the second-most at the Games. Japan's 10 gold medals lead all countries.