Nasri put them ahead early on but a sickening clash of heads between Laurent Koscielny and Sebastien Squillaci allowed Diomansy Kamara to equalise before Nasri netted a glorious winner.
Nasri's spectacular opener put the home side ahead in the 14th minute. Andrey Arshavin pounced on Aaron Hughes' error before feeding Nasri, who sold two sublime dummies before lashing the ball into the top corner.
On the half-hour mark, Squillaci and Koscielny collided going for the same ball and Clint Dempsey took full advantage of the carnage to slide in Kamara, who sidefooted home.
Koscielny was in a bad way and was carried off on a stretcher to be replaced by Johan Djourou.
Tomas Rosicky hooked a 52nd-minute volley wide as Arsenal tried to build some momentum after the restart but the winner came with 15 minutes remaining when a brilliant flowing move saw Robin van Persie square for Nasri. The Frenchman still had men to beat but did so with some unbelievable footwork, rounding Mark Schwarzer and pirouetting to net from a tight angle.
Source: PA