England manager Gareth Southgate and the FA called the troublemakers an "embarrassment" to the national team, who have been cheered on in Portugal by their biggest following since the 2006 World Cup.

"For me, it has been a real disappointment because I asked the supporters to come here and respect the country," Conniford, the FA's head of teams and corporate security, said.

"How many thousands of English people come to Portugal on their holidays and think about every single detail to make it pleasurable?

"Sadly, a group decided they weren't going to do that and that's really sad."

Just before the tournament, the FA launched a video called 'Don't Be That Idiot' highlighting the embarrassment unacceptable behaviour can cause.

That call was clearly ignored by some who travelled to Portugal and there are already fears that England's October 11 qualifier against the Czech Republic could become another flashpoint.

Scheduled to be played in Prague on a Friday evening, Conniford has questioned whether a more common-sense approach to scheduling can be taken, as is the case in domestic club football.

"Prague on a Friday night – I am not going to stand here and say I am confident about that because I'm not," he said.

"Prague is a well-known city for welcoming stag dos. I think it's tried to change that image a bit over recent years but that is a concern for me and perhaps moving forward when draws like that are made, like we do in England, if there is a potential issue then perhaps the authorities need to look at that and say, 'is England travelling to the Czech Republic on a Friday night the best thing for the game?'"

Asked if there was a better time for it to be played, he said: "I think you have to look at the whole thing in perspective.

"We went to Ireland a couple of years ago and played a lunchtime kick-off and the atmosphere, everybody said, was terrible.

"I can't remember – I just remember that we didn't have any incidents, but everyone complained that the game was just an awful event for atmosphere.

"So, there's a balance – I desperately want people to enjoy themselves.

"I want genuine people to come and everything was laid on for this to be a special event and unfortunately what we saw the other night deeply embarrassed me as an Englishman and didn't bring us any favours."

Conniford insists it is not back to the drawing board after the issues in Portugal, although clearly there is some work to do.

While he suggested legislation can be used even more, he is proud with the way things have changed and the way the 13,000 England Supporters Travel Club members are checked and punished where necessary.

But there are far more English fans in Portugal than that, with the success of Gareth Southgate's side bringing the wrong kind of people out of the woodwork.

"I don't think these individuals worry about sanctions," Conniford said.

"I don't think many of them are members. I don't think many of them want to be members.

"I think it's fashionable at the moment to follow the England team because success brings on many challenges and this is one of those challenges for us."

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