Hull FC forward Andre Savelio said a Wigan Warriors player used a racist remark during their Super League game at the DW Stadium on Thursday evening.
The New Zealander made the allegation in the 34th minute to referee James Child, who put the incident on report before the match continued.
It is not known whether the remark were directed towards Savelio, 26.
Wigan won the game 16-14 to maintain their 100% Super League record this season.
Earlier on Thursday, the Rugby Football League said it would join football’s social media boycott this weekend to tackle abuse and discrimination, with the sport’s governing body and its leading clubs and players taking part.