Surely this is a cover story to explain what will most likely be a several months long absence from the tour. I'm just kidding, but it seems to be the general train of thought around here lately.
In all seriousness, I hope it's minor and he's 100% for Dubai in a couple of weeks.
From his website:
World no.1 tennis player Novak Djokovic has cancelled his visit to Mokra Gora and Andricgrad in Visegrad due to illness.
“Virus and fatigue have taken their toll. I spoke to Emir and I’m very sorry that I’m not able to make it. I will keep my promise and visit Mokra Gora and Andricgrad when the next opportunity arrises”, Novak said.
Djokovic was supposed to visit Drvengrad (Timber Town) – a traditional village near Mokra Gora today, and then Andricgrad on Friday, the stone city project created by film director and two-time Golden Palm winner Emir Kusturica.
Kusturica wishes to present the six-time Grand Slam champion with the keys to Andricgrad as a gesture of welcome and appreciation. The stone city, also known as Kamengrad, is dedicated to the 1961 Nobel Prize Laureate in Literature, Ivo Andric.