Roger Federer and Rafa Nadal share a rivalry on court , but also a friendship off it . Sixteen-time grand slam champion says some people might find friendship strange but it 's good for tennis . Federer starts defense of Australian Open title in Melbourne this month . Comment:
Roger Federer and Rafa Nadal share a rivalry on court , but also a friendship off it . Sixteen-time grand slam champion says some people might find friendship strange but it 's good for tennis . Federer starts defense of Australian Open title in Melbourne this month . New coach Paul Annacone has urged Federer to be more aggressive .