Arsenal have launched an investigation into why hundreds of travelling supporters were delayed in getting to the Champions League Group F tie against Napoli on Wednesday night.
The Barclays Premier League club had warned their fans to take extra care in and around Naples following previous problems with the Italian side's hardcore 'Ultras' supporters.
Although special buses had been laid on to take Gunners supporters out to the Stadio Sao Paulo, so as to avoid known hot spots for trouble in the past such as the Forcella and Quartieri Spagnoli areas, many were delayed in leaving and caught up in traffic.
It resulted in several hundred missing the kick-off, with additional problems caused by late congestion outside the entrance gate.
Arsenal, who lost the match 2-0 and so finished second in their group after Borussia Dortmund's win in Marseille, have promised to look at the issues faced by their fans, many of whom used social media to highlight their experiences.
A club statement read: "We are aware of the problems our travelling supporters had on Wednesday night and in particular their late arrival at the game.
"We are very disappointed for our fans that they had a difficult evening but the circumstances were beyond our control.
"We have launched an investigation to work out precisely what happened."
The match was also notable for a protest by Greenpeace protesters, who abseiled down the main stand during the second half, unveiling a banner which read 'Giustizia per Cristian' - Justice for Cristian - in support of those detained by Russia following protests in the Arctic, specifically Naples man Cristian D'Alessandro.
Napoli fans were involved in violent clashes with their Marseille counterparts during their European tie in November, which resulted in both clubs being fined by UEFA, while a pie shop near to the Emirates Stadium was attacked by visiting Italian supporters when they played in London earlier this season.
Arsenal Independent Supporters Association had members at the match on Wednesday night.
Chair Lois Langton was not surprised to hear of security concerns from their travelling group, some of whom reported minor clashes with Napoli fans around the stadium.
She told Press Association Sport: "Until there has been a proper investigation as to what happened, it is too early to say precisely what went wrong.
"However, again, it is sadly not surprising for these sorts of issues to surface in Italy where visiting supporters are all too frequently subjected to violence, poor policing and stewarding and sub-standard conditions."
On the team's hopes for further progress, Langton feels Arsenal fans should remain positive.
She said: "While it was obviously disappointing to lose in Naples, when the group draw was made, few gave us a chance even to qualify, so it is no mean feat to have come through it.
"We often raise our game with a tough draw, like we did in 2006 against Real Madrid when not many pundits thought we would get past them and we went on to make the final."