Roger Federer pays tribute to Nelson Mandela

After almost two months of quarantine in their respective houses due to Coronavirus, professional tennis players have started training again waiting to know when they can resume the season. Unlike most of his colleagues, Roger Federer has not yet taken up his racquet. The 20-time Grand Slam champion underwent surgery on his right knee last February shortly before suspension. The Swiss Maestro has played only one tournament this year, the Australian Open, in which he reached the semifinal by