“I want to reach out and let my fans and friends know that I tested positive back in Monaco for Covid-19,” world number 19 Dimitrov wrote on Instagram.
Last weekend, Dimitrov, 29, took part in the Adria Tour event in Belgrade with Djokovic, world number three Dominic Thiem and Alexander Zverev, ranked 17.
He also played in the second leg of the Balkans tournament in Zadar on Croatia’s Adriatic coast on Saturday.
However, he withdrew after losing to Borna Coric, complaining of feeling unwell.
Later Sunday, the final between Djokovic and Russia’s Andrey Rublev was immediately cancelled as a precaution.
Zverev and former US Open winner Marin Cilic were also in the Croatia line-up.
“I want to make sure anyone who has been in contact with me during these past days gets tested and takes the necessary precautions,” added Dimitrov.
“I am so sorry for any harm I might have caused. I am back home now and recovering.”
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