Kayla Harrison tried to keep it together. Once the national anthem started, so did the tears.Harrison defeated Britain's Gemma Gibbons to win the United States' first judo gold medal in Olympic history, taking the 78-kilogram title.The 22-year-old Middletown, Ohio, native who lives in suburban Boston went to the medal podium determined not to cry. After one note of The Star-Spangled Banner, she succumbed."I'm just so honored to be America's first gold medalist, and so happy to realize my dream," she said.America's first Olympic judo champion was sexually abused by a former coach as a child, became a self-described "teenage punk" who hated everything about her sport and then found a way to turn everything around.With Russian President Vladimir Putin, himself a black belt, and British Prime Minister David Cameron among those in the VIP section, Harrison never ceded control of the final.Tagir Khaibulaev of Russia won the men's 100-kg gold, beating Beijing champion Tuvshinbayar Naidan of Mongolia with a match-ending ippon throw. Badminton: The Olympic badminton controversy continued for a third day, with the IOC demanding a deeper investigation into the scandal and defending Olympic champion Yu Yang of China apparently announcing her retirement from badminton. Tennis: Roger Federer beat American John Isner 6-4, 7-6 (5) and will play No. 8-seeded Juan Martin del Potro in the semifinals. Serena Williams advanced by beating former No. 1 Caroline Wozniacki of Denmark 6-0, 6-3. Williams' opponent in the semifinals today will be top-seeded Victoria Azarenka, who beat Angelique Kerber 6-4, 7-5. Russians Maria Sharapova and Maria Kirilenko will meet in the other women's semi. Novak Djokovic also advanced on the men's side and next plays Britain's Andy Murray. Volleyball: Captain Clay Stanley scored 19 points and the U.S. men's team defeated top-ranked Brazil 3-1 in a preliminary-round rematch of the Beijing final. The 23-25, 27-25, 25-19, 25-17 victory extends the United States' Olympic winning streak to 11 matches. Poland, Russia, Bulgaria and Italy each won in straight sets. Cycling: Germany's Miriam Welte and Kristina Vogel won the gold in sprint track cycling after the Chinese duo of Guo Shuang and Gong Jinjie was disqualified for a lane change in the final. Britain broke its own world record set earlier in the day to win its second straight gold medal in the men's team sprint.Beach volleyball: All four American teams -- two in the men's tournament and two in the women's -- finished the round-robin atop their pools, with defending gold medalists Todd Rogers and Phil Dalhausser beating the Czech Republic in the finale. Americans Jennifer Kessy and April Ross finished 3-0 with a 21-19, 19-21, 19-17 victory over Spain.Water polo: Tony Azevedo scored four goals and the U.S. men's team beat Britain 13-7 to remain undefeated. The Americans are on top of Group B with six points, one ahead of gold medal-favorite Serbia, with two preliminary stage matches to go. Serbia played to an 11-11 draw with Montenegro. The Serbs face the U.S. on Saturday. Spain, Greece, Hungary and Croatia all won.Boxing: U.S. boxers are dropping out of the Olympic tournament at a rapid rate. The American skid reached seven straight bouts with narrow defeats for lightweight Jose Ramirez and middleweight Terrell Gausha. Only welterweight Errol Spence and flyweight Rau'shee Warren -- who hasn't fought yet -- are still alive. Ramirez started slowly and never caught up in a 15-11 loss to Uzbekistan's Fazliddin Gaibnazarov, while Gausha was locked in a tight one with Beijing bronze medalist Vijender Singh of India before dropping a 16-15 decision. Ukraine's Vasyl Lomachenko opened his second Olympics in the same dominant style that made him the best boxer in Beijing, overwhelming Dominican lightweight Wellington Arias in a 15-3 victory.Rowing: The United States defended its title in the women's eight, maintaining its six-year dominance of the high-profile event.The Americans won in a time of 6 minutes, 10.59 seconds. Canada finished a half-length behind in second and the Netherlands took the bronze.The U.S. hasn't lost a competitive race in the eight since winning the world title in 2006.New Zealand picked up its first gold of the London Games when Nathan Cohen and Joseph Sullivan won the double sculls final at Dorney Lake. Italy and Slovenia grabbed the next two spots on the podium.South Africa captured its first Olympic rowing gold when its closing charge was enough to take the lightweight men's four. Britain edged Denmark for silver.Canoe: Britain took the top two spots in canoe slalom, upsetting the three-time defending champions from Slovakia.Tim Baillie and Etienne Stott won the gold, followed by teammates David Florence and Richard Hounslow.Slovakian twins Pavol and Peter Hochschorner settled for bronze. It was a stunning defeat for the Hochschorners, who have also won the last three world championships and are ranked No. 1.Emilie Fer of France was the surprise winner in women's kayak slalom. Australia's Jessica Fox took the silver, and the bronze went to Spain's Maialen Chourraut.Elsewhere: One day after upsetting Argentina at the Olympics, the U.S. women's field hockey team lost 1-0 to Australia. ... It was all China in men's table tennis, with Zhang Jike beating teammate Wang Hao 4-1 in the singles final. China has claimed 22 of 26 gold medals since pingpong was introduced at the Olympics in 1988. ... Ki Bo-bae added the individual archery title to the women's team gold she won with South Korea. Ki edged Aida Roman of Mexico in a sudden-death shoot-off to claim the top singles spot. ... British shooter Peter Wilson won the double trap gold. Hakan Dahlby of Sweden grabbed the silver, and Vasily Mosin of Russia was awarded the bronze. ... Kim Jiyeon of South Korea grabbed the fencing gold for women's individual sabre. ... Archrivals and friends Lin Dan of China and Lee Chong Wei of Malaysia each won to move closer to the men's singles final in badminton.TelevisionArchery: NBC said Thursday that during the first few days of its Olympics coverage, archery was the most popular sport of any that it aired on its cable networks -- bigger even than basketball. Archery averaged 1.5 million viewers when it came on TV.NBC Sports Group Chairman Mark Lazarus attributed the interest in part to the popularity of "The Hunger Games" getting young people interested in bows and arrows. American archer Brady Ellison is also a big draw.It is reminiscent of when recent Winter Olympics telecasts fueled an interest in curling.Tape-delayed vindicated: NBC's researchers are finding that people who know the results of London Olympics events before they are shown on tape delay are more -- not less -- likely to watch them.The preliminary research unveiled Thursday undercuts an assumption that has guided production of Olympic broadcasts from locales outside of U.S. time zones for decades. NBC has been criticized for not televising live some of the London Games' marquee events like swimming and gymnastics so they can be aired later in prime time.Two-thirds of people questioned in a survey Sunday said they watch the prime-time Olympics telecast even if they know the results ahead of time. People who watched the events live earlier in the day via computer screen watched the tape-delayed broadcast 50 percent longer than those who hadn't, said Alan Wurtzel, NBC's chief researcher.NBC has been getting far better ratings for the London Games than it ever expected, outpacing the 2008 Games in Beijing. A month ago, NBC had predicted it would lose some $200 million on the games, but network executives said Wednesday the company would break even. NBC Sports Chairman Mark Lazarus said Thursday the company could even make money if the good ratings continued.The network is airing all of the competition live via video stream. But the network's decision to hold back big events because no live competition takes place during U.S. prime time has led to widespread complaints on social media. The longtime theory was that fewer people would watch in prime time if they could see them live earlier.Lazarus held back when asked whether this would mean tape delay will become a thing of the past after the London Games."We will continue to innovate our coverage," he said on a conference call Thursday. "I won't make a proclamation here about what we are going to do, but be sure we are analyzing everything."The company Usamp questioned 1,000 adults who said they had watched Olympics competition. The survey found that 43 percent of the people who watched the prime-time telecasts said they knew the results before tuning in.Wurtzel said that the Olympics are encouraging consumers to try new things. Some 75 percent of people who said they had tried streaming Olympics coverage on tablets said they had never streamed video before on the devices.Olympics viewership was up 28 percent among teenagers over Beijing, even more sharply among teenage girls."Why is this important? Wurtzel said. "Because we're cultivating the next Olympics generation."