Arsenal were 1-0 up at Sunderland thanks to Alexis Sánchez when this 92nd-minute howler from former Gunner Vito Mannone allowed the Chilean put the game to bed by nipping in to score his second. In fairness to Mannone, the pass back from Vergini wasn't an ideal one to receive in the circumstances, but he should have been able to take a touch and clear his lines.
Sánchez had already capitalised on another dreadful back pass, by Wes Brown on that occasion, to score Arsenal's first.