Swansea are to review their matchday security operation after a Wycombe fan entered the Liberty Stadium on Saturday.
Referee Keith Stroud stopped the game in the closing minutes of the 2-2 Sky Bet Championship draw after the supporter's presence was discovered.
The official pointed out the fan and he was removed by two Swansea stewards.
"A Wycombe Wanderers supporter gained entry to the Liberty Stadium during the game before being apprehended by stadium security staff," said a Swansea statement.
"South Wales Police swiftly dealt with the person involved and he was ejected from the premises.
"While this is very much an isolated incident, the club will continue to monitor all areas of security on a matchday."
Supporters have been prevented from entering Swansea's Liberty Stadium since March 2020 because of Covid-19 restrictions.