Legia Warsaw's travelling support brought colour, noise and pyrotechnics to Stamford Bridge on Thursday night.
They lit flares and took their shirts off in celebration as the Polish club defeated Chelsea 2-1 in the second leg of the Conference League quarter-finals.
Despite the result, it is the Blues who progress to face Sweden's Djurgarden in the semi-finals of Europe's third-tier competition with a 4-2 aggregate victory.
And Legia will be bracing for trouble as they are expected to face more disciplinary action for their supporters' behaviour from governing body Uefa - adding to a long list of infractions in European competitions.