The Brisbane International organizers are "worried" that tennis star Novak Djokovic could miss the Australian event next year, according to the International Business Times AU.
The 12-time Grand Slam champion is expected to play in Brisbane next year -- which is set to take place from 31 December - 7 January.
However, the Serb hasn't yet officially confirmed that he will be preparing at Brisbane ahead of the Australian Open.
The fact that Djokovic has signed up for the Abu Dhabi exhibition -- which is due to be held from 28-30 December -- has given the Brisbane organizers some doubts.
However, they remain "confident" Djokovic will still make a comeback to Brisbane.
The 30-year-old's lost to Latvia's Ernests Gulbis in the Brisbane first-round in his lone appearance at the tournament in 2009.
The 250 Brisbane event is on the verge of having a superstar player field as Andy Murray and Rafa Nadal have been confirmed for the 2018 edition.
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