An anti-doping prosecutor had asked for a one-year ban but Mutu's representatives argued he should serve just a three or four-month suspension because they said he consumed sibutramin by accident in a herbal laxative medicine.
The tribunal announced the nine-month ban at a court hearing in Rome but given he has been serving a provisional suspension since failing the two drugs tests in January, the 31-year-old will be able to return to action at the end of October.
"I'm not happy. Such a long ban for a laxative pill seems really excessive," Mutu said in a statement read out to reporters by his lawyer Paolo Rodella, who said the player may now appeal to the Court of Arbitration for Sport (CAS).
Mutu, who was sacked by Chelsea in 2004 for cocaine use and served a seven-month ban, has been sorely missed by Fiorentina with the Florence side sliding down to 10th in Serie A and being knocked out of the Champions League last 16 by Bayern Munich.
The former Parma and Juventus player is still dealing with the consequences of the 2004 cocaine scandal, as Switzerland-based CAS backed Chelsea's claim for compensation last year and ordered him to pay over 17 million euros in damages.
He is appealing against the ruling to a Swiss federal court and the situation is now on hold.
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