The Football Association (FA) is looking into allegations that Mansfield Town striker Adi Yussuf urinated in view of supporters during their League Two match against Plymouth Argyle.
Yussuf is reported to have relieved himself during Saturday's match at Home Park, which ended in a 3-0 win for Plymouth.
The Plymouth Herald received an account of events from a witness the newspaper stated wished to remain anonymous.
"During the first half of the match Mansfield substitute Adi Yussuf was warming up on the touchline right in front of the disabled zone," the unnamed fan told the newspaper.
"He said something to Plymouth Argyle substitutes [Louis] Rooney and [Ben] Purrington before walking over to the piece of disused land between the disabled zone and the Devonport End and took a wee.
"This was right in front of everyone in the disabled section. Myself and the lady who works in the refreshments area witnessed it as well as some others and we reported it to the stewards.
"They later took a statement and reported it to the referee."
The clubs have been contacted by the FA for further information on the allegations.
"The FA are aware of the incident and have contacted the two clubs for their observations," an FA spokesperson stated.
In a statement, Mansfield Town said: "The club has been made aware of the said complaint by The Football Association and is internally investigating the matter."
A Plymouth Argyle spokesperson said: "We were asked for our observations by the FA on an incident during our game against Mansfield that was included in the referee's report. We have complied with this request and await developments."