I guess his performances at Juventus and Portugal spring to mind, but I'm going to refrain from turning this into a Messi v Ronaldo thread like we've seen before!He joined United the summer after they had won the league for the 8th time in 12 years, he joined Real after they had won the league 2 out of the 3 previous seasons and he joined Juventus after they had won their 7th consecutive title. Not sure what your idea of dragging a team across the finishing line is but that looks very much like joining teams at the height of their success.
Can't blame Aguero for wanting out from the mess that is Barcelona, but he must have known what he was getting himself into to some degree surely!?