Novak Djokovic and his wife Jelena have pledged one-million euro to help fight the spread of COVID-19 in his home country of Serbia.
The money will be used to purchase ventilators and other medical equipment for front-life staff at hospitals across the country.
"Unfortunately, the number of those infected is increasing," the tennis world number one said of the decision to make the donation.
"Jelena, myself and my foundation, have decided to gather as much relevant information as possible this week to determine how best to donate our resources - knowledge, time, money, how it will affect the largest number of people across Serbia".
Djokovic says he will lean on business contacts in order to secure protective equipment and respirators from companies in China and Europe.
"Through my uncle Goran, who has an influential network of people in the Chinese market, we were able to reach the producers directly, waiting for specific information about the quantity so that we could make a donation, and my parents have good contacts in Europe, primarily in Germany."
Roger Federer and wife Mirka also pledged one-million Swiss Franks to help contain the virus in Switzerland this week while Raga Nadal and Spanish basketball player Pau Gasol are currently fundraising in a bid to raise 11-million euro in Spain.