Federer and Serena power into quarterfinals

Roger Federer of Switzerland changes his shirt during a break in his men's singles match against Milos Raonic of Canada at the Australian Open tennis tournament in Melbourne, Jan 21, 2013. [Photo/Agencies]

Roger Federer of Switzerland celebrates defeating Milos Raonic of Canada in their men's singles match at the Australian Open tennis tournament in Melbourne, Jan 21, 2013. [Photo/Agencies]