Millwall manager Kenny Jackett insists his club has done everything in its power to root out the troublemakers who have wrecked the club's reputation.
Investigations are continuing into the ugly scenes that scarred Saturday's FA Cup semifinal defeat to Wigan at Wembley.
While the vast majority of Lions fans upheld a general improvement in behavior since the ugly days of the 1980s, 12 were arrested for their part in the disgraceful outbreaks of fighting.
Millwall have vowed to take the strongest action against those found to be responsible.
But Jackett feels there is only so much the club can do.
"We will continue to work hard," he said. "Whether we ever do it [get rid of the reputation] is a tough call.
"I have been here a number of years and am very proud of the way everyone has worked at the club. There has been a considerable amount done. The board of directors have worked in every direction they possibly can, making sure the players go out into their local community.
"It is a disappointing day," he said.
Four police officers received minor injuries in the trouble, some of which was shown live on TV.
Two Wigan supporters were also arrested, although they were not involved in clashes with Millwall counterparts.
A Metropolitan Police spokesman said four of the arrests were for affray, one for affray and possession of Class A drugs, one for affray and assault on police, two for public order offenses, one for assault causing actual bodily harm and possession of Class A drugs, one for a racially aggravated public order offense, one for ticket touting, one for possession of Class A drugs, one for theft and possession of offensive weapon, and one for breach of banning order.
"There will be a significant post-match review and further investigation will take place to identify those responsible for committing offenses," a police spokesman said.
There has already been criticism in some quarters for the evening kickoff time, which offered supporters the chance to consume an excess of alcohol.
Privately though, the FA do not feel this is a significant issue given the number of high-profile matches at the stadium that have had evening kickoffs, including, two seasons ago, a Manchester derby semifinal, and last year an all-Merseyside encounter.
In addition, Millwall featured in League One playoff finals in both 2009 and 2010 and both passed off peacefully.
It is for this reason that officials of the south London outfit do not believe the fact that some tickets were put on general sale will prove to be significant in the trouble as they have adopted exactly the same procedure in the past.