Novak Djokovic vs Alexander Zverev live stream, Italian Open
Tennis - ATP - Rome Open - Novak Djokovic of Serbia v Dominic Thiem of Austria - Rome, Italy- 20/5/17- Djokovic returns the ball. Reuters / Stefano Rellandini

Former World No. 1 Novak Djokovic has left organisers of the Brisbane International worried after announcing his decision to enter the Abu Dhabi exhibition in late December. In the build-up to the 2018 Australian Open, Djokovic was expected to play the Brisbane International (Dec.31 - Jan.7).

While the organisers of the ATP World Tour 250 series event are still confident about Djokovic's participation, they are still to get confirmation from the 12-time Grand Slam champion.

World No. 1 Rafael Nadal and World No. 3 Andy Murray have confirmed their participation at Brisbane. Since Nadal is also playing the Abu Dhabi exhibition between Dec.28-30, there's no reason why Djokovic can't do the same. Djokvic, ranked No. 7 in the world, will likely receive a first-round bye and not start his Brisbane International campaign before Jan. 4. The organisers are banking on that.

Novak Djokovic confirms return at Abu Dhabi exhibition

“The line-up (in Abu Dhabi) is very strong and it will be the perfect way to make my comeback. The whole thing about my tennis and what happened to me is more complex than a single word, although that (the elbow) was the biggest problem, I could not train like I wanted, could not play with full intensity. I did not want to take a break, but the problems were intensifying," Djokovic said recently while announcing his decision to return from his career-threatening elbow injury.

Geoff Quinlan, the tournament director at the Queensland Tennis Centre, has declined to comment on the chances of Djokovic joining Nadal and Murray at the Brisbane International.

Meanwhile, Murray has agreed to return to Brisbane after a five-year absence, two months after he called off his 2017 season due to a hip injury. “The ball was still coming out of the middle (of the racquet). I can’t wait to get back competing -- I miss it so much,’’ Murray said on social media.

The comebacks of Andy Murray and Novak Djokovic would bode well for tennis after Roger Federer and Rafael Nadal, the other two members of the sport's Big 4, dominated grand slam tennis through 2017. While Federer prevailed at the Australian Open and Wimbledon, Nadal clinched victory at the French Open and U.S. Open.