Jose Mourinho has revealed that Diego Costa is furious with reports linking him with a return to Spain.
The Spanish international joined the Blues last year in a £32 million deal and bagged 20 goals to help his new side win the Champions League, while he also scored in the Capital One Cup final victory over Tottenham.
Despite his successful first campaign reports in Spain claimed this week that he was seeking an exit from Stamford Bridge because he is unhappy with life in London and has refused to settle in - something he emphatically denied yesterday.
The Brazilian-born ace told reporters of a potential return to Atletico Madrid: "It's quite a simple answer. It’s always a bit more difficult for adaptation in the first season, but I have no reason to leave this place, I love it, the fans love me and I want to stay."
"It’s really good to come in the first season and win two things. It’s really important and next year I’ll be ready to come back and hopefully win a couple more trophies."
Now Mourinho has revealed the details of Costa's reaction to the reports, claiming that he took exception to the suggestion that he wanted to leave.
'I’m happy he’s unhappy because his unhappiness destroys my dressing room," he said.
"He is the guy responsible for every single good moment in the dressing room. He is so happy, he is so funny and he is enjoying every minute at Chelsea and people are enjoying every single minute of him. So if this is unhappiness I am happy with that. But he was not happy with that news. In his bad English I think he has to try to express how unhappy he is with this news and how happy he is at Chelsea."
Costa claimed the man of the match award in Chelsea's 1-0 post-season win over Sydney FC yesterday - however it wasn't all good news as the 26-year-old was forced from the pitch after 40 minutes with a hamstring complaint.
Loic Remy scored the only goal of the game, while Mourinho was fuming at youngster Ruben Loftus-Cheek, who managed less than half hour on the pitch before being subbed off claiming a back injury.
"Ruben was saying he had a pain in his back but what I was feeling was that he only had this pain when Sydney had the ball,” the Special One said.
“When Chelsea had the ball he was playing very well but when Sydney had the ball I think he was more impressed by watching [John] Mikel Obi and [Nemanja] Matic work, instead of him working himself. So, with Ruben, it’s one step back in terms of my relationship with him. If he doesn’t know what it means to play for me and Chelsea, it’s one step back.
Diego Costa is perhaps the Premier League wind-up merchant, and if he's angered by the reports then Mourinho will be praying he holds on to that feeling until the new season starts.
It seems staggering that he could want to leave Chelsea where he just won the league title and is working under one of the most successful coaches in Champions League history - even if he isn't loving London all he needs to do is stay put for a few years, win more trophies and collect a massive pay-cheque.