Swansea condemned Arsenal to a 2-0 home Barclays Premier League defeat as Michu fired in two late goals at Emirates Stadium.
The Gunners had been second best for long spells, and despite an improved performance after the break, the Swans earned reward for their persistence when Spain forward Michu grabbed a late brace.
Jeers greeted the final whistle at Emirates Stadium, as manager Arsene Wenger's side dropped more points and fell further behind in the battle to break back into the top four.
Wenger opted to deploy Ivory Coast forward Gervinho in the central striker role ahead of Theo Walcott, but it was Swansea who were the first to press, with a free-kick into the Arsenal penalty area eventually being hacked away by Per Mertesacker.
In the 14th minute Arsenal goalkeeper Wojciech Szczesny made a fine double save after Angel Rangel had been played in on the overlap down the right and fired in a low, angled drive with his follow-up effort also blocked by the agile Pole.
The hosts finally got some momentum, with Santi Cazorla heading at Swans goalkeeper Gerhard Tremmel after a good cross from Carl Jenkinson. Nathan Dyer suddenly burst clear through on goal from a flick by Miguel Michu, but Arsenal captain Thomas Vermaelen made up the ground to produce a brilliant sliding block.
Eight minutes before the break Michu was bundled over by Mikel Arteta at the edge of the Arsenal penalty area, but Jonathan de Guzman whipped his free-kick up over the wall, and also the crossbar.
Arsenal emerged with much more vigour for the restart as Cazorla shot straight at the goalkeeper following good work by Jack Wilshere and Gervinho's run to the edge of the Swansea box was halted by Chico, but referee Mark Clattenburg waved play on.
With 24 minutes to go, Wenger made a double change as Olivier Giroud and Alex Oxlade-Chamberlain replaced Podolski and Gervinho. French striker Giroud was put clean through straight away, but was caught by a desperate lunge from Chico which was ruled fair by the referee.
Substitute Dwight Tiendalli forced a block from Szczesny before the visitors took the lead when Michu broke clear after a neat one-two with substitute Luke Moore to slot past Szczesny. It got worse for the Gunners in stoppage time when Michu latched onto a long clearance, racing through to beat the keeper again.