ROME (AFP) - Italian former Olympic swimming champion Federica Pellegrini accidentally left her address and mobile phone number for all to see when she posted a photograph on Twitter on Friday.

The 27-year-old Pellegrini, whose Twitter account @mafaldina88 has 455,000 followers, tweeted on Friday morning that she had been subjected to a random doping test and posted a photo of documents relating to the control.

The slight problem was that her number and address were clearly visible on the documents.

Almost immediately, she received numerous tweets urging her to hide the number, although others asked if they could add her on messaging app whatsapp.

Pellegrini still hadn't deleted the tweet by Friday afternoon.

One of Italy's leading sports stars, Pellegrini won the Olympic 200m freestyle title in 2008 in Beijing and is a four-time world champion, taking the 200m and 400m freestyle titles in both 2009 and 2011.

She also holds the 200m freestyle world records over short and long course.