Do you even know why he said that? Cause Jiraiya was a guardian of Konoha. There was no point in fighting him. P.S I don't see how Jiraiya would counter Kisame's water either.Itachi said those words to kisame and I quote ."kisame if we fight one on one with him we might die , if both of us intervene we might win but we will have too much damge" well its not the same words as itachi but similar