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 Quick Recap of this morning's action 
 
 Women's 50-meter freestyle 
 
 Netherland's go 1-2 with Ranomi Kromowidjojo and Marleen Veldhuis (24.51 and 25.57, respectively). 
 
 Great Britain's Francesca Halsall was third at 24.61 and USA's Jessica Hardy was 12th with a time of 24.99. American teammate Joyce Kara Lynn lost the swim-off against Britain's Amy Smith for the final qualification spot. 
 
 Men's 1,500-meter freestyle 
 
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 China's Sun Yang swims an impressive race finishing in 14 minutes and 43.25 seconds to win the prelims. He's less than 10 seconds from the world record, so it is a realistic possibility. 
 
 South Korea's long distance man Park Taehwan gets sixth in the qualification at 14:56.89 and USA's Connor Jaeger was seventh at 14:57.56. 
 
 Women's 4x100 medley relay 
 
 Australia has a strong lead going into the final with a time of 3:55.42 which is more than two seconds faster than second-place Japan (3:57.87). 
 
 The USA took fourth in the prelims at 3:58.88, just 0.53 behind Denmark who was third. 
 
 
 
 
 
 Men's 4x100-medley relay 
 
 Unsurprisingly the U.S. won the men's prelims with a time of 3:32.65. 
 
 As the only ones to break 3:33.00 flat, expect the Americans to make a run at the world record because the rest of the field will be battling for silver and bronze. 
 
 From Great Britain (second at 3:33.44) to the Netherlands (fifth at 3:33.78) is just a 0.34 differential between four countries. The final will be immense. 
 
 What to watch for later today, action begins at 2:30 p.m. ET. 
 
 Women's 50-meter freestyle semifinals 
 
 The Netherlands as mentioned above went 1-2 and are reasonably expected to hold onto that standard. 
 
 USA's Jessica Hardy and Australia's Campbell sisters have a lot of quick catching up to do, though. Therefore, you can anticipate this race being potentially faster than the final as one length of the course will bring out the best in each competitor. 
 
 Women's 200 backstroke final 
 
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 USA's Elizabeth Beisel and Missy Franklin went 1-2 in the semifinals and are more than 0.50 seconds ahead of Australia's Meagen Nay (third in semis). 
 
 Expect the Americans to joust for gold while bronze remains up for grabs. 
 
 
 
 
 
 Men's 100 butterfly final 
 
 Michael Phelps swam the fastest semifinal time of 50.86 seconds and is well ahead of South Africa's Chas le Clos who bested him in the 200 fly. 
 
 That said, don't think le Clos will just let Phelps breeze in the final. 
 
 
 
 
 
 Women's 800 freestyle final 
 
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 Great Britain's Rebecca Adlington is at the front of the pack after the prelims with a time of 8:21.78. Right behind her was Denmark's Lotte Friis at 8:21.89, so these two will stream ahead for gold. 
 
 The story here, though, is USA's Katie Ledecky who was third in the prelims and is only 15 years old. 
 
 
 
 
 
 Men's 50 freestyle final 
 
 It'll be a race for the ages despite the short length. 
 
 USA's Cullen Jones and Brazil's Cesar Cielo tied at 21.54 for the fastest semifinal swim. Only 0.08 seconds behind is Cullen's teammate Anthony Ervin at 21.62 and 0.01 after him is Cielo's teammate, Bruno Fratus. 
 
 Two countries vying for three spots with two representatives. It will be fun. 

 Here are the highlights of the London Olympics on Friday: 
 
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 United States' Missy Franklin reacts to her gold medal win in the women's 200-meter backstroke final at the Aquatics Centre in the Olympic Park during the 2012 Summer Olympics in London, Friday, Aug.... (Associated Press) 
 
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 1. MORE GOLD: Michael Phelps won a 17th gold in 100 butterfly, his final individual race in London. 
 
 2. MISSY FRANKLIN: The American teenager set a world record in the 200 backstroke for her third gold and fourth medal overall. 
 
 3. CYCLING: In team pursuit, the British took gold and beat their own world record set only a day earlier. 
 
 4. TENNIS MARATHON: It took a while, but Roger Federer beat Juan Martin del Potro of Argentina 3-6, 7-6 (5), 19-17 in 4 hours, 26 minutes. He will go for gold on Sunday against either Andy Murray or Novak Djokovic. 
 
 5. GOING HOME: Russian track cyclist Victoria Baranova was expelled for failing a pre-Olympics doping test. And an Australian rower was sent home after damaging two shopfront windows in an alcohol-related incident.
– Michael Phelps won the 100-meter butterfly at the London Games today for the record 17th gold and 21st medal overall in his Olympic career. In the final individual race of his career, Phelps was next to last at the turn but then produced his usual furious finish to clock 51.21 seconds. Phelps will end his career with the 4x100 medley relay tomorrow. Also of note: Missy Franklin set a world record in the 200 backstroke for her third gold and fourth medal overall. American 15-year-old Katie Ledecky won the 800-meter freestyle. The youngest member of the US swim team narrowly missed a world record in the grueling race, falling off pace on the last lap and finishing in 8 minutes, 14.63 seconds. It took a while, but Roger Federer beat Juan Martin del Potro of Argentina 3-6, 7-6 (5), 19-17 in 4 hours, 26 minutes. He will go for gold on Sunday against either Andy Murray or Novak Djokovic. Russian track cyclist Victoria Baranova was expelled for failing a pre-Olympics doping test. And an Australian rower was sent home after damaging two shopfront windows in an alcohol-related incident. See Bleacher Report for more details and updates.