Novak Djokovic has added Croatia’s Borna Coric and Marin Cilic to his upcoming Adria Tour.

The tour will move across the Balkans and Bulgaria's Grigor Dimitrov, Austria's Dominic Thiem and Germany's Alexander Zverev are alreeady in the line-up.

The event will start in Belgrade on June 13 and 14 and will be behind-closed-doors as the country is still not allowing large gatherings due to the coronavirus pandemic.

The world No 1 said of the event: “I'll do everything in my power to be a good host.”

From Belgrade, the tour will move to the Croatian town of Zadar with Bosnia-Herzegovina and Montenegro on the cards to host the final two legs.

Each stage will have two pools with four players and whoever wins each event will progress through to the final.

Djokovic has just returned to Serbia after being forced to remain in Spain as he was visiting his brother when lockdown rules were enforced.