A six-year-old boy was hit in the head by a rock and another man was injured after a brawl involving at least 10 people broke out during the trial match between the Sky Blues and NSW state league club Macarthur in Campbelltown.
Police are still investigating the incident, but it is understood a group, who claim to follow the Wanderers, sparked a fight by throwing a flare at Sydney fans which was then thrown straight back.
Gorman was quick to distance the A-League's newest club from the group that started the trouble, but said it was important to come down hard on those responsible.
"Last night was not about fans from Western Sydney Wanderers or fans from Sydney FC or fans from the A-League, these are thugs who will come and infiltrate any area to express their anti-social behaviour," Gorman said at a joint press conference with Sydney FC chief executive Tony Pignata today.
"It's a societal thing, as you've seen in a raft of areas in recent times. But we've got to address it as a club and in a collaborative effort with Sydney FC and the whole A-League.
"If we identify the culprits they will be hit as hard as we can.
"We'll obliterate them from the game, we won't have it in our venues. Our venues will be ones where mums and dads and kids can feel safe."
He added: "There's fruit loops out there that will go to any endeavour at all to undermine this sport because they just don't care and when you deal with people that don't care it's a very challenging set of circumstances to confront.
"We need a united approach to do that. This is the premier game of football in Australia and we need to turn into safe, entertaining environment where anyone can feel comfortable coming.
"These are thugs in a sporting environment to make grief and they achieved that.
"I don't care what they were acting like, our job is to obliterate them from the game and we will."
The Wanderers host Sydney FC in the first local derby on October 20 and it now seems certain security will be stepped up for the Parramatta Stadium clash to avoid any problems.
Pignata said both clubs' sets of fan groups would meet before the season.
"There's a lot of anger among both sets of fan groups about what happened last night [Tuesday] because it's a bad reflection on them and not what they're about," the Sydney boss said.
"I'm confident there won't be any more incidents arising.
"It's time we get rid of these thugs out of our game and leave us alone.
"It's a great game and we want to promote to families they are not to be allowed to be at any of our games if it causes these sorts of issues."
Asked if the injury to the young boy could affect families attending matches, Pignata said: "There was a lot of parents around there with their small children and they would have been traumatised from what their kids saw.
"To see 10 guys running at each other would be scary.
"We need to show them this is an isolated incident and then welcome them back to the A-League."