Chelsea's Antonio Rudiger is believed to be unimpressed with his side's negotiations over a new contract, according to reports.
The German's current deal at the Blues expires next summer, meaning he would be able to leave the club as a free agent should he not sign a new contract.
However, it appears that talks have not yet progressed as much as he'd like.
According to SPORTBILD via Sport Witness, Rudiger is becoming frustrated with the 'lack of effort' being shown by the club during talks.
The reports suggests that the demands made by the centre-back are those that the Blues are unwilling to meet.
Negotiations are believed to have been ongoing for months now but there is still no agreement between the two parties.
It is thought Bayern Munich and Real Madrid would be interested in acquiring the 28-year-old should he leave Chelsea next summer.
Rudiger joined Chelsea from Roma in 2017. He has since won winners' medals in the FA Cup, Europa League, Champions League and Super Cup.
He has made 159 appearances during that time, and his performances in the Blues' Champions League winning run last season have made him of the side's most crucial players and one of the best in his position.
As well as the German international, Andreas Christensen, Cesar Azpilicueta and Thiago Silva all see their contracts expire next summer. Recent reports suggest an agreement is close with Christensen, but there is no news as of yet in regards to Azpilicueta and Silva.
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