West Ham's new signing, Ravel Morrison, has defended his "homophobic" tweet, claiming that racial abuse made him react badly.
The West Ham youngster, who joined from Manchester United on deadline day, said that he called someone a "f****t" after he was labelled a "black f****t" and a "crackhead".
He defended his outburst as a kneejerk reaction.
The Football Association wrote to the Hammers and Morrison over the tweet. It will consider its response this week and Morrison could find himself facing disciplinary action.
The FA's guidelines on social media stipulate: "Any comments which are deemed improper, bring the game into disrepute, or are threatening, abusive, indecent or insulting may lead to disciplinary action.
"Comments which are personal in nature or could be construed as offensive, use foul language or contain direct or indirect threats aimed at other participants are likely to be considered improper."
West Ham purchased him for an undisclosed fee on the last day of the January transfer window.
United reportedly sold him because they couldn't keep up with his wage demands.