#2 Thierry Henry
Thierry Henry is one of the greatest strikers of all-time. Arsenal was lucky to have him for eight long years but lost him to Barcelona in 2007. With 228 goals, the Frenchman is the all-time top goal scorer in the Gunners history.
Thierry Henry was the most important player of the great Invincibles squad of 2003/04. Ever since his departure, Arsenal's supremacy in the Premier League has vanished slowly. Though Arsenal had a great striker in Robin van Persie, a player like Thierry Henry can never be replaced.
Henry went on to win two La Liga titles and a UEFA Champions League title with the Catalan side. Arsenal could have won a few more Silverwares had Henry stayed at the club for a few more years.