Thomas Muller has be warned against a move to Premier League champions Chelsea as speculation grows that the German has been added to Jose Mourinho’s shopping list.

Fresh reports this morning claim the Blues are ready to battle long-term admirers Manchester United for the Bayern Munich forward in the summer with question marks over the future of Diego Costa.

Costa cut a forlorn figure at White Hart Lane on Sunday as Mourinho dropped the Spanish international following a disappointing start to the season for the man who took England by storm last year.

He even appeared to throw his training bib towards Mourinho in the dugout when taking his seat following a warm-up along the touchline.

Chelsea will not punish the striker for his show of petulance but he remains on thin ice after scoring just four times this term and clashing with his boss during the win over Maccabi Tel-Aviv last week.

Rumoured Blues January transfer targets in pictures:

Muller, according to The Mirror , is being earmarked as a possible replacement but former Bayern midfielder Lothar Matthaus doesn’t think it would be a good idea for his compatriot.

“He does not need Manchester United or Chelsea,” said Matthaus. “Barcelona perhaps could use him, but I do not know whether he can deal with their game.

“My opinion is that he should definitely stay at Bayern for his lifetime.

“He started his professional career at Bayern and I think he should end his career here. He does not need any new challenge as he is always playing at the highest level every year at Bayern.”

Muller joins a long line of forwards to be linked with the Blues as Mourinho is also said to be keen on with Jamie Vardy, Saido Berahino, Antoine Griezmann and Shakhtar’s Alex Teixeira all being considered.

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