1/ Itachi's Genjutsu can be dispelled by experimented ninja with good chakra control.
2/ Itachi's Susanoo can be destroyed by big ball rasengans.
3/ Itachi's Amaterasu can be sealed and Jiraiya did that already.
4/ Itachi is a low chakra ninja and his jutsus consume so much chakra while Jiraya has immense chakra reserves so as long as the battle goes Jiraiya will get more chances to win.
5/ As I said Itachi must end the battle quickly which is impossible against Jiraiya.
6/ The only problem for Jiraiya is Tsukuyomi so he must summon toads to undo it or use shadow clones to avoid that.
I know that many won't agree but that's the way it is =D
2/ Itachi's Susanoo can be destroyed by big ball rasengans.
3/ Itachi's Amaterasu can be sealed and Jiraiya did that already.
4/ Itachi is a low chakra ninja and his jutsus consume so much chakra while Jiraya has immense chakra reserves so as long as the battle goes Jiraiya will get more chances to win.
5/ As I said Itachi must end the battle quickly which is impossible against Jiraiya.
6/ The only problem for Jiraiya is Tsukuyomi so he must summon toads to undo it or use shadow clones to avoid that.
I know that many won't agree but that's the way it is =D