The world No. 3 is looking relaxed ahead of Shanghai. (AP)

Novak Djokovic is living it up these days as the reigning US Open and Wimbledon champion. He's laid to rest all the doubts about his ability to return to the top and sits at No. 3 in the world, behind his usual rivals Rafael Nadal and Roger Federer.

As he awaits the start of his next challenge in Shanghai, Djokovic has kept busy. 

He practiced "The Floss" dance with a young prodigy, Mihailo Topic. 

And reconnected with his roots by spending time with his mentor Niki Pilic.

 
 
 
 
 
 
 
 
 
 
 
 
 

Niki Pilic, my tennis father. My mentor. His wife Mija and him accepted Jelena Genčić’s request for me to come to his academy in Germany when I was 12 years old even though he usually did not accept players under 14. He had one of the best European tennis academies at the time. Mija and Niki treated me as their own child and did the same for my 2 younger brothers. My family will always remember that. _ Niki is 80 this year and he still plays tennis 4h a day. His mindset is remarkable. He is healthy and super passionate about tennis - court is his home. He was a very successful player and even more successful coach. He is the only tennis coach to win 5 different Davis Cup titles with 3 different nations (Germany, Croatia, Serbia). _ Niki is one of the most important tennis and life mentors I’ve ever had. My time spent in his academy has greatly impacted my game and career. I am eternally grateful Mija and Niki for everything you have done for me and my family ????????❤

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And had a little fun with Albert Einstein on his way to Shanghai.

 
 
 
 
 
 
 
 
 
 
 
 
 

On my way to #Shanghai, I reconnected with an old friend. We talked Universe, intelligence, vibration, frequency, energy... You know, the usual “stuff” ???? He was mostly keen on talking about how great Nikola Tesla was. Dear Albert, it was nice to see you again. Thank you for sharing your wisdom with me and leaving such a great legacy behind ???????????? _ Na putu za Šangaj, sreo sam starog prijatelja. Pričali smo o tajnama Univerzuma, vibraciji, inteligenciji, frekfencama, energiji.. Znate, one uobičajene, svakodnevne “teme” ???? Najviše je želeo da razgovaramo o tome koliko je veliki Nikola Tesla bio. Dragi Alberte, lepo je bilo videti te opet. Hvala što si sa mnom podelio mudrost i znanje i što si iza sebe ostavio veliki legat ????????????

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He also made time for some carrot cake.

Djokovic has qualified for the ATP Finals in London, but Shanghai will have valuable ranking points as he has none to defend from last year.