Dominic Thiem took part in the Belgrade leg of the exhibition event organised by Novak Djokovic, where matches were played in front of thousands of fans, earning a storm of criticism.
Novak Djokovic's coach Goran Ivanisevic also contracted coronavirus last month.
Novak Djokovic donated the money to Novi Pazar, in Serbia's southwest, to help it fight a growing outbreak of the disease.
After testing negative for coronavirus, Alexander Zverev had released a statement vowing to self-isolate, only to be spotted at a busy bar, apparently over the weekend, in footage that went viral.
Goran Ivanisevic is part of Novak Djokovic's coaching team and was the director of the now-abandoned Adria Tour which led to several top players becoming infected with the coronavirus.
Dominic Thiem took part in the Belgrade leg of the exhibition event organised by Novak Djokovic where social distancing was minimal and matches were played in front of thousands of fans.
Nick Kyrgios, Dominic Thiem and Alexander Zverev have been signed up to take part in Berlin.
Novak Djokovic was widely condemned for hosting a tennis exhibition where he was one of four players to test positive for the coronavirus.
World number one Novak Djokovic joined Grigor Dimitrov, Borna Coric and Viktor Troicki in contracting COVID-19 following the Adria Tour event which saw minimal social distancing.
Novak Djokovic has been criticised for hosting the exhibition tournament that has led to a slew of players testing positive for coronavirus, including himself.
Novak Djokovic appears doomed never to be held in the same saintly esteem as Roger Federer or Rafael Nadal, the undisputed 'people's champions' of tennis.
World no.1 Novak Djokovic released a statement saying he has tested positive for coronavirus.
Viktor Troicki became the third tennis player from Novak Djokovic's Adria Tour tennis tournament to test positive for coronavirus.
Novak Djokovic came under extreme criticism after two players tested positive after playing an exhibition tennis tournament.
Croatian tennis player Borna Coric has tested positive for coronavirus a day after Grigor Dimitrovs positive test led to the cancellation of the Adria Tour final.
Grigor Dimitrov said Sunday he has tested positive for coronavirus, just a week after he played an exhibition tournament alongside world number one Novak Djokovic.
LeBron James dropped a "beautiful" remark on Novak Djokovic's basketball skills.
Novak Djokovic had initially voiced unease over the United States Tennis Association's intention to keep the event starting on August 31 at Flushing Meadows despite New York being the hardest-hit city by the US coronavirus crisis.