World 100 metres freestyle champion swimmer James Magnussen is gambling on a new coach taking him to Olympic gold in Rio de Janeiro in 2016 after parting ways with his long-time mentor Brant Best. The 23-year-old Australian successfully defended his title at the world championships in Barcelona last year but missed out on gold in the blue riband sprint at the 2012 Olympics in London by a fingertip. "Brant has been such an important part of my journey as a professional swimmer, and in shaping me as person," Magnussen said in a statement on Tuesday. "As I launch into this next competitive block, I have resolved that in order to refocus my program, and to achieve a sense of renewed invigoration, part of that change process involves working with a new coach." Best, the high performance coach at the New South Wales Institute of Sport, guided Magnussen through his breakthrough season of 2010 and the following year prepared him for his stunning victory at the world championships in Shanghai. Click here to read full news..