RIO DE JANEIRO, Jan. 4 (Xinhua) -- Brazilian tennis player Thomaz Bellucci has been banned for five months after failing a doping test.

The 30-year-old tested positive for the diuretic and masking agent hydrochlorothiazide during the Swedish Open in July, the International Tennis Federation (ITF) said on Thursday.

It added that Bellucci was not guilty of any "significant fault or negligence", accepting that the result was due to contaminated vitamin supplements.

The ban has been backdated to August, meaning the world No. 112 is free to return on February 1.

Bellucci, who reached a career high of 21 in the rankings in 2010, said: "I could never imagine that a multivitamin made by a pharmacy could suffer crossed contamination in minimal amounts. I always took care and respected the rules."