Last month the centre-forward was reportedly involved in a training ground bust-up with Antonio Conte over a prospective move to China.
The Brazil-born hitman was then dropped from the Chelsea squad that travelled to the King Power Stadium to face champions Leicester on January 14.
Intense speculation still surrounds the striker’s future, however, with reports in Spain suggesting that he has already agreed a pre-contract agreement with a Chinese club in the summer,
But Costa has decided to hit back with a straight-talking message on social media.
“They talk too much shit!!!” the 28-year-old posted on his Instagram account, once in Portuguese and repeated in English. “Come on Chelsea!!!”
Costa is the Blues’ top goalscorer with 15 Premier League goals so far this season. Don't mess with 'im.
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