Exeter Chiefs apologised to former England international Ugo Monye after he accused a supporter of racist abuse at Sandy Park on Sunday.
The 40-year-old was working at the match as part of the punditry team on TNT Sport.
Monye posted on X, formerly known as Twitter, that he experienced “the most blatant racism I’ve seen from a supporter at a live game”.
“So fed up,” he wrote, adding that the incident happened as he was leaving the ground and “not a single person said a word, challenged or even reported it”.
Exeter and Gloucester gave their backing to the former centre, who won 14 caps for England.
Chiefs said they would be “launching a full investigation” and offered “sincerest apologies” to Monye, adding: “This behaviour will not be tolerated at our rugby club.”
Gloucester said they would “encourage a thorough investigation and will co-operate fully to ensure the culprit is identified”.
Premiership Rugby said in a statement: “Racism has absolutely no place in our game or society.
“Premiership Rugby offers our full support to Ugo Monye and we stand united with our clubs and players in the fight against racism.”