(ABC NEWS) -- Michael Phelps broke the record for most career Olympic medals with a U.S. gold in the men's 200-meter relay in an eventful day four in the London Games.
After the United States won its first Olympic gold medal in women's gymnastics since it hosted the 1996 Games in Atlanta, the greatest drama of the day moved to the pool, where Phelps was touched out at the wall by Chad le Clos of South Africa in the men's 200-meter butterfly.
Phelps appeared poised throughout that race to pick up his 15th career gold medal and become the first swimmer to win a gold medal in a singles event in three consecutive Olympics, but the South African snuck up on Phelps in the last few seconds.
Upon realizing his defeat, Phelps, who had yet to win a gold medal in London, slapped the water and tossed his cap in disgust. But he was all smiles less than an hour later, when the U.S. relay team's dominating performance made him the most decorated Olympian of all time. His split was the fastest of the team, at 1:44:05, just over a second faster than Ryan Lochte's time, which gave the Americans a solid lead from the beginning.
Phelps surpassed Soviet gymnast Larisa Latynina, whose 18 medals, 9 of them gold, made her the winningest Olympic athlete for 48 years. Swimmer Mark Spitz held the American record before Phelps with 11 medals, just one more than track star Car Lewis.
American Allison Schmitt won the gold in the 200-meter freestyle, shattering the record with a time of 1:54:61. The bronze narrowly escaped her teammate Missy Franklin, the high school senior who won Monday's 100-meter backstroke.
The United States took the bronze in the women's 200-meter medley, with Chinese 16-year-old Ye Shiwen coming from fourth place to win a gold medal that will likely add to a swirl of doping suspicions surrounding her record-breaking performances. Ye finished in 2:07:57, nearly a second faster than her record time in the semifinals.
The U.S. women gymnastics team stepped into the arena Tuesday night in the shadow of overwhelming media hype. Not since Atlanta's "Magnificent Seven" had the U.S. women's gymnastics team been the subject of such high expectations. But the team led throughout the event, beating Russia by a wide margin, with Romania earning the bronze.
The Chinese, defending the gold medal they won in 2008 in Beijing, finished fourth.
The team gold was redemption for Jordyn Wieber, the star American gymnast who failed to qualify for the individual event.
Away from the gymnastics mat and the pool, tennis provided the most riveting moments of the day.
Venus Williams and Maria Sharapova advanced, while Andy Roddick crumbled to Novak Djokovic.
But the Tuesday's most exciting matchup was between less-famous names. Jo-Wilfried Tsonga of France won the longest set ever played in the Olympics over Canadian Milos Raonic after 48 games.
Serena Williams, fresh off her fifth victory at Wimbledon earlier this month, announced that she would forgo the mixed-doubles event in order to play with Venus in the regular doubles. Serena Williams will also compete in the women's singles event.
On the soccer field, all it took was one goal by Abby Wambach to take the U.S. women's soccer team to a hard-won victory over North Korea. Goalkeeper Hope Solo, who caused controversy recently with her Twitter criticism of NBC commentator and former U.S. soccer star Brandi Chastain, staved off several threats to the U.S. shutout in the game's second half.
Although the North Korean women are ranked in the top 10 internationally, their restricted interactions with other teams have kept them largely anonymous in women's soccer.