The NRL integrity unit has been notified of an altercation between Reece Walsh and a young fan just days out from the grand final.
In a video posted to TikTok, a Penrith supporter calls out to the star Brisbane fullback as he left the NRL's grand final fan day at Circular Quay in Sydney on Thursday afternoon.
According to the clip's caption, the supporter told Walsh that Penrith prop Moses Leota was "gonna take his head off" in Sunday's decider between the Panthers and Broncos.
The brief video ends with Walsh telling the fan "I'll take your mum's" and walking away.
The NRL integrity unit told AAP they had been made aware of the incident but that no investigation had yet been launched.
"The NRL integrity unit is aware of the matter," a spokesperson said.
Walsh has become one of the NRL's most popular stars in his first season since joining Brisbane from the Warriors, but has previously run afoul of the league for his fiery temperament.
He received a three-game ban for swearing at referee Chris Butler during a match against Gold Coast in late June, ruling him out of contention for the Dally M Medal.
He was also sent off during the second State of Origin clash after a passionate exchange with NSW five-eighth Jarome Luai in which both men head-butted each other.