Chelsea say they have identified and banned a season ticket holder indefinitely after reports that Tottenham forward Son Heung-min was racially abused at Stamford Bridge.
The incident is alleged to have happened when the South Korean international went to take a corner in the second half of Sunday's 2-2 draw in the Premier League.
In a statement earlier this week, the west London club said discriminatory behaviour was "totally abhorrent".
It added at the time: "Chelsea FC has consistently made its zero tolerance position on discriminatory behaviour very clear, yet there are still idiots like this that attach themselves to this club as so called 'fans', which shames Chelsea FC, our coaches, players, staff and our true supporters.