A new fitness regime including yoga and the influence of his new manager Simon Fuller are being credited with helping to propel Andy Murray into the Australian Open final. It was the new Andy Murray. Gone was the surly, wild-haired young man we saw at Wimbledon. In his place at the Australian Open last week was a smart, smiling and confident star-in-the-making, charming the media and winning a legion of admirers on and off the court. On Sunday morning the new Murray was fighting to change the record books, taking on Roger Federer and attempting to become the first British man for 74 years to win a Grand Slam singles title. Tennis insiders said Murray's transformation could be put down to several factors: his new manager Simon Fuller, the fitness regime introduced by Team Murray – including Bikram yoga – and the ending of the relationship with his long-term girlfriend, Kim Sears. Many in the game were surprised last year when Murray signed up with Fuller's 19 Entertainment rather than a global sports agency such as IMG, which boasts clients including Federer and Tiger Woods.