New boy Nasri opened his account with the London club as early as the fourth minute, steering home Denilson's pass from six yards out.

West Brom feared the worst that their Premiership return would be marred by a comprehensive scoreline at Emirates Stadium, but the home side remained quiet for the rest of the first half.

The Gunners did not extend their lead after the break, despite Robin Van Persie's introduction as a second half substitute.

The Dutchman could have doubled the lead in a couple of occasions, but Arsenal settled for the one-goal win.