Manchester United boss Sir Alex Ferguson has registered his interest with Fiorentina for defender Matija Nastasic.

Fiorentina coach Delio Rossi says the young Serb can develop into a better defender than United captain Nemanja Vidic.

Ferguson is well aware of Nastasic's rising star and Calciomercato.com says he made a bid for the youngster in January.

Fiorentina threw out the offer, but know Ferguson won't shelve his interest in centre-half.