Arsenal's 4-1 win over Galatasaray was illuminated - and disrupted - by visiting supporters throwing flares onto the pitch.
Although flares have been dealt with by other countries across the continent, in England they are still regarded as an unsettling presence. And at 2-0, flares were launched onto the pitch.
Galatasaray captain Wesley Sneijder sought to diffuse the tension by jogging over to the visiting support and appealing for calm. It didn't inspire the visitors, but it made for one helluva sight...