Town said anyone found to have thrown a missile would be indefinitely banned from the ground – and claimed the incident could have led to the game being abandoned. They said there was now the possibility the club could face a fine, a points deduction or even a stadium closure.
Crawley won 3-2 to go sixth in League Two but the incident involving the former Peterborough, Portsmouth and Tottenham keeper has overshadowed the win.
A statement from the Reds warned fans such behaviour would not be tolerated. The club said: “Crawley Town Football Club unequivocally condemns the behaviour from select individuals in the South Terrace during today’s fixture against Tranmere Rovers.
“Upon Crawley equalising in the 61st minute, a large group of ‘supporters' proceeded to launch a number of missiles in the direction of the Tranmere Rovers goalkeeper. Behaviour like this is unfathomable and will not be tolerated.
"The club have already launched an internal investigation and anyone found to be throwing missiles of any kind onto the field of play will be indefinitely banned from the Broadfield Stadium and may face wider football bans.
“Owing to the behaviour of these supporters, there was a very real possibility of the game being abandoned at 1-1, a scenario that was only avoided owing to the response from the club security team. First team players and staff have also lodged their displeasure at these scenes owing to the stoppage in play that ensued as a result of the fans behaviour which lost the team momentum when the impetus was with them.
“The club will now likely receive a sanction from the FA which will provide significant financial stress for the club - something that could be better spent to ensure the continued progress of the team.
"Other potential sanctions include stand and stadium closures as well as points deductions. Unfortunately owing to the continual bad behaviour of a select group of fans, these are now very real sanctions that the club could face in the coming weeks.
"The support this season home and away has largely been superb, however it is exceedingly disappointing, and now concerning that these select groups, who do not represent the wider fan base, continue to let the club down in this way.
“Crawley Town Football Club wishes to formally apologise to Luke McGee and Tranmere Rovers for the abuse suffered this afternoon and will be making no further comment at this stage.”