The world's top-ranked tennis player, Novak Djokovic, celebrated his 33rd birthday on May 22.

With professional tennis shut down due to the novel coronavirus pandemic, the world No.1 has decided to bring together some of the world's top players for a series of matches to run from June 13 to July 5 in the Balkan region.

All pro tennis tours were suspended in early March and the ATP official has suspended the tour until July 31 as countries went into lockdown and closed borders to contain the spread of the virus.

Some players, including the 33-year-old Serbian, have returned to the practice courts while maintaining strict hygiene and social distancing rules.

Some exhibition events without fans have also been held in countries including Germany and the United States.

World number three Dominic Thiem of Austria and Bulgarian Grigor Dimitrov, who is ranked 19, have confirmed their participation in the eight-man event which will end with Djokovic's exhibition match against Bosnian Damir Dzumhur in Sarajevo.

Croatia, Montenegro and Bosnia will be the other venues for the matches, which will be broadcast on television. 

The world No.1 posted on Twitter that "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."

He also expressed his gratefulness that the tour could take place and support humanitarian projects across the region.

Djokovic, who won his 17th Grand Slam title at the 2020 Australian Open, is 18-0 this year in all matches.

He lifted the ATP Cup with Serbia, 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.

(Cover: Novak Djokovic trains in Marbella, Spain, May 18, 2020. /VCG)