Avon and Somerset Police have launched an investigation after Bristol City's Famara Diedhiou was racially abused online.
The Robins striker was targeted after missing a penalty in his side's loss at Swansea on Saturday.
The Senegal international hit the post from the spot in City's 1-0 defeat at the Liberty Stadium, a result which officially ended their chances of reaching the Sky Bet Championship play-offs.
After the game the 27-year-old posted a screenshot on his Twitter page of another user who sent him a message consisting of three banana emojis.
Diedhiou accompanied the picture with the word "Why??" and the police are now involved in the matter.
"We're aware of racist social media message directed at a Bristol City FC player and a formal report has been made to us," a statement from Avon and Somerset Police read.
"Our football liaison officer has been in touch with the club to offer support and confirm an investigation will be carried out. They will be speaking to the affected player in due course to take more details and extend this support directly to him.
"We've contacted Twitter to ensure the post is removed and to get further details about the offender. Early indications suggest the message may have originated from an account holder outside of this country.
"Racist messages of any kind are abhorrent and we want to reassure the player and the club that a full and thorough investigation will now take place."
City also tweeted: "We stand with Famara Diedhiou and anybody who has to suffer racism in any shape or form. There is no excuse or justification for this disgusting behaviour."
The incident comes after two Premier League players – in Crystal Palace's Wilfried Zaha and David McGoldrick of Sheffield United – were reportedly racially abused on social media last weekend.
It is also the third time this season where City players have been racially abused online after incidents involving goalkeeper Jojo Wollacott and midfielder Korey Smith.