SYDNEY, Sept. 6 (Xinhua) -- Australians have thrown their support behind the nation's new tennis hero, John Millman, before his battle with Novak Djokovic in the U.S. Open semifinals on Thursday.

Millman shot to legend status when he defeated tennis great Roger Federer in the fourth round of the U.S. open on Tuesday.

Now the 29-year-old former office worker has another giant of the sport to face in the form of Novak Djokovic.

Aussie fans took to social media to throw their support behind Millman before he takes to the court in what will be the biggest match of his life.

Supporters told Millman to "stand tall" and "enjoy the moment," reminding him that no matter the outcome, just to get there is an extraordinary achievement.

As well as the chance to square up against tennis royalty, Millman will walk away with a guaranteed 475,000 U.S. dollars for making it to the semifinals.

While the odds are stacked against him, if Australia's enthusiasm for their new tennis hero is anything to go by, Millman has all the support he needs.