For a long while this season, Arsenal have looked an unstoppable force.
They arrived at Sunderland on Saturday looking to extend their winning run to 11 consecutive games and keep a club-record ninth clean sheet in a row.
Victory would have sent them eight points clear at the top by the end of the day, but the Black Cats that crossed the Gunners' path at the Stadium of Light were set on being disruptive.
Regis le Bris' side, the pre-season relegation favourites, have surpassed all expectations on their return to the Premier League and are sitting pretty in the European places for now.
They used everything in their power to unsettle and ultimately shock the league leaders, earning a 2-2 draw that will have been celebrated far beyond Wearside.
Sunderland scored the first goal Arsenal have conceded since September when Dan Ballard gave them a first-half lead, and although the hosts then slipped 2-1 behind, there was a late twist as Brian Brobbey scored a dramatic injury-time equaliser, sparking wild scenes of celebration on the pitch and in the stands.
From moving advertising hoardings to "creating chaos", here is how Sunderland achieved such an impressive result.