Men's world No 1 Novak Djokovic has launched a tennis series to take place in the Balkan region in June and July as professional tennis remains in lockdown during the coronavirus pandemic. All professional tennis tours were suspended in early March and will not return before August as countries went into lockdown and closed borders to contain the spread of the virus. The shutdown has caused the cancellation of numerous tournaments, <a href="https://www.thenational.ae/sport/tennis/coronavirus-wimbledon-championships-2020-cancelled-1.1000395">most notably Wimbledon</a> for the first time since the Second World War. Some players, including Djokovic, have returned to the practice courts while maintaining strict hygiene and social distancing norms, and some exhibition events without fans have also been held in countries like Germany and the United States. "I'm proud to officially share the news that the #AdriaTour will be held across the #Balkans 13 June - 5 July kicking off with a tournament in Belgrade," Djokovic, who turned 33 on Friday, said in a Twitter post. "Very grateful we could make this happen to play and support humanitarian projects across the region." World No 3 Dominic Thiem of Austria and Bulgarian Grigor Dimitrov, who is ranked No 19, have confirmed their participation in the eight-man event which will end with Djokovic's exhibition match against Bosnian Damir Dzumhur in Sarajevo, the capital of Bosnia and Herzegovina. Zadar, in Croatia, Montenegro and Banja Luka in Bosnia will be the other venues for the matches, which will be broadcast on television. Djokovic, who won his 17th Grand Slam title at the 2020 Australian Open, has been 18-0 this year in all matches. He led Serbia to the inaugural ATP Cup, won an eighth Australian Open title and then completed a fifth triumph at the Dubai Tennis Championships, extending his unbeaten run to 21 matches dating back to last season. Djokovic was also at the centre of a fund launched to raise funds for players struggling financially during the lockdown - a fund to which, incidentally, Thiem said <a href="https://www.thenational.ae/sport/tennis/dominic-thiem-says-struggling-tennis-players-don-t-deserve-his-hard-won-money-1.1011287">he would not contribute</a>.