Danish tennis pro Caroline Wozniacki has been accused of being 'racist' after she did an impersonation of Serena Williams during an exhibition match.

The former world number one tried to entertain the crowd in Brazil while playing against Maria Sharapova by stuffing towels down her top and skirt to give her a more shapely figure.

While the stunt was perceived by some as a joke, others blasted the 22-year-old for being disrespectful.

The Daily Mail quotes a blogger on Tumblr as saying: "This isn't 'harmless fun' as one article described it. its racist. out and outright racism. mocking and making fun of the bodies of black women for a laugh? real funny, stupid white girl. real real funny."

Williams was also in Brazil to promote the 2016 Games.