World Sambo Day celebrates the anniversary of the creation of the sport, which has now been contested for 82 years. 

Shestakov addressed the sambo community in a letter on the FIAS website and described the challenges the sport had endured this year. 

"The outgoing year 2020 turned out to be difficult, unlike all other years," he said.

"The COVID-19 pandemic, which has hit the whole world, has become a real test not only for sambo, but also for other sports. 

"Self-isolation, quarantine and total closure of borders made it impossible to hold international tournaments, and national championships were also under threat. 

"Athletes lost the opportunity to perform at competitions and fight for medals, and the audience - to enjoy spectacular fights."

Shestakov detailed how sambo had coped with the challenge of the pandemic, including the staging of four online continental competitions. 

The eight finalists from each tournament were able to compete against each other virtually in a super final. 

Novi Sad in Serbia was also able to host the World Sambo Championships and the World Youth and Junior Sambo Championships earlier this month. 

"This was made possible thanks to the great efforts of the Sambo Federation of Serbia, the Serbian Government and the administration of Novi Sad," Shestakov said.

"In order to minimise the risks of COVID-19 to athletes, the competition was held for the first time without spectators, in conditions of isolation of all team members from any external contacts. 

"Fortunately, such strict but necessary security measures paid off - the competition was successful, and all the teams returned home safely." 

Shestakov ended his letter with a positive message. 

"This year, thanks to all of you, our favourite sport was able to cope with new challenges," he said.

"Thanks to your active participation, your desire and your contribution to the common cause, sambo continues to develop and win the hearts of people of all ages in the most remote corners of the globe."

Other celebrations of World Sambo Day included the unveiling of a statue at the Luzhniki Sports Complex in Moscow.

The statue is in tribute to three founders of sambo - Vasily Oshchepkov, Victor Spiridonov and Anatol Kharlampiev.

A bust dedicated to Oshchepkov was also revealed in the Russian city of Novosibirsk earlier this week.

Sambo was registered as a sports discipline in the Soviet Union on November 16 1938.