Chelsea are investigating alleged racist abuse directed at Son Heung-min during Sunday's 2-2 draw with Tottenham.
The South Korean forward started the London derby and played 79 minutes before being replaced by Yves Bissouma.
The incident is believed to have taken place in the second half when Son went over to take a corner at the Shed End.
Son has experienced racist abuse before during his time in England.
Back in 2019, a West Ham fan was fined for racially abusing him during a Carabao Cup match.