The fiery Chelsea star was shown a second yellow card by referee Michael Oliver after 84 minutes following an altercation with the Everton midfielder in which he moved his head towards his opponent and appeared to place his mouth on his neck in an attempted bite.
However, Costa was adamant that there was no foul play after a defeat which effectively ended Chelsea’s season.
“Diego spoke to club officials after the game and expressed regret over his reaction to the challenge from Gareth Barry that led to his red card,” said a Chelsea statement.
“But Diego was also very clear that he did not bite him at any point during that altercation.”
To add to the late drama at Goodison Park, Barry was also booked in the flashpoint and received a second yellow card of his own in the dying minutes after fouling Cesc Fabregas.
Interim manager Guus Hiddink refused to condemn Costa after the first sending off of his Chelsea career.
The Dutchman even managed to laugh off the incident, with reference to the Hollywood movie “Anger Management”.
“There are movies about that,” said Hiddink when asked if he will advise his player to seek counselling.
“I have seen that film. Maybe we will go and watch it together. I try to be fair in my judgement and I haven’t see it so far. But without wanting to give a judgement, he was chased a bit in the game as well.
“They went after him, they know it. It’s within the rules but, as a referee, you must protect the situation a little bit. I’m not saying ‘PROTECT’ with capitals, but knowing and feeling the atmosphere, the little provocations.”
Any punishment by the English Football Association will depend on referee Oliver's report although Hiddink repeated his often-stated position of insisting he does not want Costa to alter his combative style.
"I like him," said Hiddink, who praised Costa for wanting to play despite suffering injury in the midweek Champions League loss to Paris Saint-Germain.
“I still like he is going towards the edge but you also have to take into consideration he desperately wanted to play today. It would have been better for him to be rested but this was not the type of game where you rest players.”
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