I have a lot of problems with Ryan Reynold’s Green Lantern movie, and his training on OA is one of them. In the film, all he did was go 1 on 1 with Kilowog and suddenly that makes him a certified Green Lantern? They should have devoted at least 30 minutes of the film having his ass kicked in training. Makes more sense for an origin movie as opposed to him defeating a crazed Guardian of the Universe (I refuse to call that creature Parallax).
From – Green Lantern Vol. 4 #31