Bristol Rovers are investigating claims that midfielder Jordan Goddard urinated in front of visiting Corby Town fans during their FA Cup clash.
Substitute Goddard is said to have relieved himself near the corner flag as he warmed up during the game at the Memorial Stadium on 12 November.
The 18-year-old went on to make his first-team debut in the 3-1 win.
Avon and Somerset police confirmed they were aware of the claims and are now speaking to Bristol Rovers.
Corby Town supporter James Crawford told BBC Radio Bristol that he had witnessed the incident: "There was three or four of them warming up and then one lad just pulled himself out and urinated on the floor, right in front of us.
"There was a lot of people shouting at him but he just looked over and started laughing."