I think Arsene Wenger is a competent manager...But, his key players were injured...Bad luck...Guys like Van Persie, Rosicky, and Eduardo...Remember Eduardo broke his leg in a game against Birmingham...A Birmingham defender tackled Eduardo very hard...
Cry me a river.. Every team loses key players and you have manage around the problem. Arsenal lost fewer than most this season.
Look at West Ham (9 players injured), look at Chelsea losing 5 key players to the African Cup of Nations for 6 weeks, as well as having Ballack out for 4 months, Joe Cole out for two months, Carvalho out for 6 weeks, Cech out for 4 weeks, Lampard out for 4 weeks....
Injuries are no excuse for Arsenal's failure (again) this season.