The Gunners were caught ball watching and completely stunned after a breach in their goal within 19 seconds.
The half time team talk must have been severe as Arsenal came back out with a strength and determination that had earlier been lacking.
Goals from both Santi Cazorla and Aaron Ramsey put the north Londoners in a stronger position but after going down to ten men due to Chambers being sent off, time ran out and the Potters gained a famous win.
Arsenal finished the weekend in sixth with their top four hopes dented and now have to pick themselves up in Europe – and here are five things Wenger needs to sort out.
Click on Sanchez to see what we think they need to do.
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