Former world No. 1 Marcelo Rios has labeled Novak Djokovic as the “king of stupidity” as the Chilean tennis legend is having a hard time understanding how the Serb is willing to compromise his chances of finishing as the greatest of all time because of “some vaccines.” Djokovic, a 20-time Grand Slam champion, was denied participation at the Australian Open because of his vaccination status. Rafael Nadal took the advantage of Djokovic’s absence and won a record 21st Grand Slam. Djokovic has stated that he is willing to miss tournaments that introduce mandatory vaccination. “I don’t know what the reason i …