World No 1 Caroline Wozniacki insisted on Tuesday that she was not making fun of Rafael Nadal when she imitated the Spanish superstar's cramping spasm at the US Open.

"Had a bit of fun last night b4 my press conference. Hope it was not taken the wrong way. I have the upmost respect and admiration of Rafa!!!!," said the Dane on her Twitter account.

Nadal slid to the floor in agony during a news conference after his fourth-round win over David Nalbandian on Sunday, slipping slowly off his chair and disappearing behind a table.