Michael Phelps headed into retirement with another gold medal — the 18th of a mind-boggling career, bringing his overall medal haul to 22 — as the U.S. won the 4x100-meter medley relay. After the race, the president of international swimming's governing body gave Phelps a silver trophy as the most decorated Olympian.

— Serena Williams became only the second woman to achieve a career Golden Slam, winning the most lopsided women's final in Olympic history by beating Maria Sharapova 6-0, 6-1. Williams lost only 17 games in six matches en route to her first singles gold medal. The career Golden Slam was first achieved by Steffi Graf, who did it when she won at the Olympics in 1988 after sweeping all four major titles.

— Venus Williams has a shot at a record fourth tennis gold Sunday, while sister Serena will try for a weekend double when they play Andrea Hlavackova and Lucie Hradecka of the Czech Republic in the doubles final. The Williamses clinched at least a silver by beating Maria Kirilenko and Nadia Petrova of Russia in the semifinals.

— Americans Bob and Mike Bryan completed a career Golden Slam by winning the men's doubles, beating Jo-Wilfried Tsonga and Michael Llodra of France 6-4, 7-6 (2). The three-time Olympians won the bronze in 2008. They've won 11 major titles and finished 2011 ranked as the No. 1 doubles team for the seventh time in nine years.

— The U.S. team of Missy Franklin, Rebecca Soni, Dana Vollmer and Allison Schmitt set a world record to win the women's medley relay. The 17-year-old Franklin, who starts her senior year in high school this fall, finished the meet with four golds and a bronze, while Schmitt leaves with three golds, a silver and a bronze.

— "Blade Runner" Oscar Pistorius, the first amputee to compete in track at the Olympics, easily qualified for the 400 meters in a season-best time of 45.44 seconds.

— Jamaica's Shelly-Ann Fraser-Pryce made it back-to-back Olympic titles in the women's 100, closing ground in the last 20 meters and leaning at the line to win in 10.75 seconds and edge American Carmelita Jeter by 0.03 second. Fraser-Pryce became the first woman to repeat in the 100 since Gail Devers of the U.S. did it in 1992 and 1996.

— China's Sun Yang shook off a false start and then set another world record to win the grueling 1,500-meter freestyle — the longest event in the pool — with a stunning time of 14:31.02. That beat his mark from last year's world championships by 3.12 seconds.

— It was a big night for Britain at Olympic Stadium, with three track gold medals for the hosts in about an hour. First, Jessica Ennis won the 800-meter run to secure the heptathlon title. Greg Rutherford continued the British roll in the men's long jump, and Mo Farah won the men's 10,000 meters.

— Britain confirmed its status as rowing's dominant nation with two golds on the final day of the regatta. Victories in the men's four and the lightweight women's double sculls took the host country's tally of golds to four, one more then New Zealand. Britain's rowers finished with nine medals — four golds, two silvers and three bronzes — to surpass the country's record total of eight from the 1908 Olympics, also held in London.

— Midway through the London Games, the United States is locked in a tight battle with China in the ultimate Olympic competition — the race for No. 1 in the medals. The U.S. leads by one medal on each list — 26-25 in golds and 54-53 overall. Host Britain has 14 golds and 29 overall, third in both categories. In the battle for the next few spots, South Korea has surged into the top four and Russia and Australia are lagging behind expectations.

Britain lost to South Korea in a penalty shootout in men's soccer, a bitter disappointment for the host nation in the sport it invented. South Korea advances to a semifinal against Brazil, while Britain lost its bid for a medal after a 52-year absence from the Olympics.

Ilya Ilyin of Kazakhstan won the gold medal in weightlifting in the 94-kilogram class, nailing all six of his lifts and breaking two world records. His training secret? "I try not to eat anything which is too fat, and I can't eat anything which is too sweet. I think chicken and horse meat are ideal food because it's very easy to digest." Horse meat is a Kazakh delicacy.

— Gymnastics: individual event gold medal finals in men's floor exercise, men's pommel horse, women's vault.

— Track and field: gold medal finals in men's 100 meters, women's 400 meters, women's triple jump.

— Women's diving: springboard gold medal final.

— Beach volleyball: quarterfinals.