Novak Djokovic has appealed for help for his flood-hit native Serbia.
Djokovic, who is playing at the Italian Open tournament in Rome, tweeted Saturday: "Support for everyone! Let's help the endangered! Join the aid action!"
Tens of thousands of people have been forced out of their homes in Serbia and in Bosnia. At least 20 people have died.
Djokovic is facing Milos Raonic in the semifinals in Rome on Saturday.