Chelsea boss Jose Mourinho has played down suggestions that Diego Costa wants to leave Stamford Bridge.
It has been reported that the 26-year-old is unsettled in London and will push for a return to Atletico Madrid this summer.
Failure to adjust to life in London has been picked out as the main reason for Costa's reported struggles, but Mourinho has claimed that the Brazilian-born Spanish international "is the happiest guy in the dressing room".
"He's the guy responsible for everything good we have in the dressing room. He's so happy, so funny, he enjoys every minute and is the happiest guy in the dressing room," Mourinho told reporters.
"If this is unhappiness I'm happy with that. He was not happy with the news."
Costa scored 21 goals in 34 games for Chelsea during the 2014-15 campaign.
