Leeds United are at the centre of a Football Association racism investigation after Charlton Athletic alleged that their on-loan forward Jonathan Leko was abused by a member of Marcelo Bielsa’s team last Saturday. The player in question is understood to be the 32-year-old Spanish goalkeeper, Kiko Casilla.

The incident took place during the Championship match won 1-0 by Charlton and was included in the report of the referee, John Brooks, to the FA. That submission has prompted the governing body to speak to the clubs and individuals concerned before determining whether there is a case to answer.

Leko is on loan at Charlton from West Brom – who were due to face Leeds in another second tier game on Tuesday night – and much will hinge on what he tells the FA. In a statement confirming that the allegation had been reported to Brooks during the match the south London club said they would be supporting the 20-year-old throughout the investigation. Like Charlton, Leeds were not prepared to comment further than to say they would be “working with the FA”.

Under rules introduced for the 2019-20 season, the minimum suspension for a player found guilty of an aggravated breach of the FA’s discrimination rules is now six matches, which can be increased depending on any additional aggravating factors.

Sophie Jones of Sheffield United women was handed a five-match ban this year after being found guilty of racially abusing Tottenham’s Renée Hector. Jones, who denied the charges and maintained her innocence throughout, left United by mutual agreement in March.

Kick It Out, the anti-discrimination group, has also offered its support to Leko, who was born in the Democratic Republic of Congo and is an England Under-20 international.