The Serbian represented his country in a revamped version of the Davis Cup in Spain at the tail end of 2019, an event which Roger Federer chose to boycott due to reforms overseen by Barcelona footballer Gerard Pique.
Djokovic also led Serbia victory at the newly-formed ATP Cup in Australia in January but believes that in future he will be made to make a choice between the two competitions.

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"In my opinion, they have to merge," he told reporters in Dubai.
"That’s necessary because for me personally it will be very difficult to play every single year both competitions, so I’m going to have to choose."
Djokovic is the top seed at the Dubai Duty Tennis Championships and is set kick off his campaign at the tournament against Philipp Kohlschreiber. He is also playing doubles alongside Marin Cilic.
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