Chelsea have been told to up their bid for VfB Stuttgart defender Antonio Rudiger.

Stuttgarter Zeitung says Chelsea have already made their opening bid for the 22 year-old - to the tune of €10 million.

However, Stuttgart rate Rudiger at €18 million and have told Chelsea to try again.

Chelsea's move for Rudiger is expected to see young defensive duo Kenneth Omeruo and Tomas Kalas move on.

Both players have been linked with a move to Germany.