Wycombe goalkeeper Jordan Archer was attacked by a fan in the closing stages of his side's 1-0 League Two win over Gillingham at the Priestfield Stadium.
The 19-year-old - who is on loan from Tottenham - was placing the ball prior to taking a goal kick when the supporter entered the field and leapt towards him.
The fan was quickly apprehended by a steward and led away.
"Some people give the rest of the Gillingham fans a bad name," Wycombe boss Gareth Ainsworth told Sky Sports 1.
"I don't want to comment too much, but everyone is okay in there."
Ainsworth later added: "He (the fan) will be dealt with by Gillingham and the authorities.
"I want to concentrate on the football really, what he did was wrong and he's given the rest of the Gillingham fans a bad name and they'll be as annoyed as anyone.
"I don't think it hurt the keeper. Jordan's a tough lad."
Gills boss Martin Allen was quick to condemn the incident.
He said: "As a football club we can't condone (what happened). None of us are happy with that. Our supporters have been fantastic but for one person to do something like that is crazy.
"I'm sure when he wakes up he'll be shocked, disappointed in himself. It's not a true reflection of the club since I've been here."