AC Milan turns down Chelsea's 'significant offer' for Romagnoli

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Chelsea's pursuit for a central defender hit another snag Thursday, as AC Milan rejected a "significant offer" from the Blues for highly rated Italian centre-back Alessio Romagnoli.

The bid reportedly amounted to €40 million, including potential add-ons, but the Rossoneri said the player is off the market.

"AC Milan has received a significant offer for its player Alessio Romagnoli from Chelsea FC," read a club statement. "The player is not for sale, therefore this negotiation will not continue. The club wants to thank Chelsea FC, with whom we will continue to have a great working relationship."

The 21-year-old only joined Milan last summer in a €25-million deal from AS Roma, signing a contract with the club until 2020. He's considered a future starter with Italy, having already represented his country at various youth levels.

Chelsea has so far failed to recruit a defender before the end of the transfer window, with negotiations for Napoli's Kalidou Koulibaly also proving to be unsuccessful. The west London outfit is reportedly capping its bid for the Senegalese at around €45 million.

Torino's Nikola Maksimovic is considered a backup for the Blues, and the Serbia international appears the likeliest to sign out of the three Serie A players. Maksimovic has refused to train with Torino as he tries to force his way out of the club.

The 24-year-old is expected to cost around €25 million.

With Kurt Zouma expected to be sidelined until 2017, Chelsea can only count on John Terry, Gary Cahill, Branislav Ivanovic, and Cesar Azpilicueta as senior options in defence.