Novak Djokovic was spotted at an ATP 250 event.

Novak Djokovic was spotted in the stands at the Belgrade Open

Novak Djokovic was spotted in the stands at the Belgrade Open (Image: @novakfanclub)

Novak Djokovic surprised the tennis world by turning up to an ATP 250 tournament on Sunday.

After skipping the Paris Masters, the world No. 5 was spotted in the stands of the Belgrade Open which is being staged at his Novak Tennis Centre.

It comes as his ATP Finals chances remain up in the air. Djokovic is currently sixth in the race to qualify but appears to have ended his season and has been tipped to pull out.

Djokovic’s immediate future looks uncertain. The 37-year-old has not played a match since competing at the Six Kings Slam exhibition. His last official ATP Tour outing was at the Shanghai Masters more than three weeks ago, where he reached the final.

Novak Djokovic of Serbia poses for a photo with the trophy...

Novak Djokovic is the defending champion of the ATP Finals (Image: Getty)

Afterwards, the 24-time Major winner admitted he didn’t know what his plan was for the rest of the season. He subsequently pulled out of the Paris Masters, leaving his chances of qualifying for the ATP Finals in doubt.

But nobody was able to surpass him in the race to Turin last week and Djokovic remains in sixth place, with the top eight qualifying.

However, the defending champion has been tipped to pull out with Greg Rusedski saying he would be “surprised if [Djokovic] plays in Turin or plays any more tennis this season.”

Rusedski’s comments come after Djokovic had previously admitted that he was “done” with tournaments like the ATP Finals before photos emerged of the Serb vacationing in the Maldives.

But the world No. 5 is now back in Europe and was spotted attending the Belgrade Open on Sunday. Videos showed the Olympic champion signing autographs for fans in the stands following Hamad Medjedovic’s first-round victory over sixth seed Brandon Nakashima.

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It’s no surprise Djokovic turned up in Belgrade even if he has no plans to play. The event is held at his tennis centre in his hometown and his brother Djordje is the tournament director.

But with the world No. 5 now back in Europe and taking an interest in tennis, it could be a sign that he is considering heading to Turin if he remains in one of the top eight spots.

However, there are plenty of players attempting to overtake him this week. Alex de Minaur, currently eighth in the race, is competing in Belgrade to get some extra ranking points in his quest to make it to his first ATP Finals.

Meanwhile, Andrey Rublev and Casper Ruud are in action at the ATP 250 in Metz. Ruud is currently No. 7 in the race while Rublev is ninth, just outside the cut-off.

But if Djokovic announces that he won’t be returning to Turin to defend his crowd, the player in ninth place will get in.