World number five Andrey Rublev is the fifth player to test positive for COVID-19 after playing at an exhibition event in Abu Dhabi this month.
Spaniard Rafael Nadal, Canadian Denis Shapovalov, Switzerland's Olympic champion Belinda Bencic and Tunisian Ons Jabeur all tested positive after taking part in the event.
US Open champion Emma Raducanu tested positive in Abu Dhabi before the event and withdrew, while Nadal's coach Carlos Moya also contracted the novel coronavirus.
The 24-year-old Rublev, who beat Andy Murray in the World Tennis Championship final on December 18, confirmed on Twitter he was isolating with minimal symptoms.
"I am currently in Barcelona and unfortunately tested positive for COVID-19," the Russian said. "I am in isolation and following all the protocols under the supervision of doctors.
"As you know, I am fully vaccinated and was preparing for tournaments – ATP Cup and Australian Open. Now I have to recover and I will go to Melbourne only when it will be safe for everyone."
The Australian Open will be held at Melbourne Park from January 17. Rublev was part of the Russian team that won the men's ATP Cup this year and had been included in the team for the upcoming edition in Sydney, which kicks off on Saturday.
Thiago Agustin Tirante has rallied past Novak Djokovic 2-6 6-4 6-4 at the Cincinnati Open on Saturday, as the Serbian struggled in the heat and required a medical timeout in a disappointing US Open tune-up.
Islam Makhachev (29-1 MMA) has successfully defended his UFC welterweight championship Saturday night, defeating Ireland's Ian Machado Garry (17-2 MMA) via unanimous decision (49-46, 49-46, 48-47) while also setting an impressive record in the main event of UFC 330 in Philadelphia.
Germany's Johannes Liebmann has smashed the world record for the men's 1500 metres at the European Aquatics Championships on Saturday, knocking almost four seconds off the previous record in a dominant display.
Inter Milan have signed England international winger Djed Spence from Tottenham Hotspur on a contract running until June 30, 2031, the Serie A club said on Saturday.
New Zealand ran in eight tries as they thumped South Africa’s Bulls 50-19 in their latest Rugby’s Greatest Rivalry tour fixture in Pretoria on Saturday, an impressive warm-up ahead of the first test against the Springboks next weekend.
Dr Anwar Gargash, diplomatic advisor to the UAE president, said the repeated targeted attacks on ADNOC tankers will not deter the UAE from moving forward with a 'balanced and rational policy' backed by diplomacy, deterrence, and adherence to international law.
Dubai Customs has completed a major international seizure by foiling an attempt to export over 70 million illicit cigarettes that were en route to a European country.
The UAE has expressed its solidarity with Indonesia following the tragic 7.7-magnitude earthquake that struck its eastern region on Saturday, killing at least 38 people and injuring 13 others.