Venus and Serena Williams have clinched at least a silver medal in doubles with a victory in the Olympic semifinals. The sisters beat another sibling pair, Ukraine's Alona and Kateryna Bondarenko, 4-6, 6-4, 6-1, on Saturday. The Williams sisters improved to 9-0 lifetime in Olympic doubles. They won the gold medal at Sydney in 2000 but didn't play doubles in 2004 because Serena was hurt. More...