LOLImpossible
Did not the great Itachi die against pre-MS Sasuke?
What manga are you reading? Itachi clearly let Sasuke win and at the end Itachi died due to his diseases not by Sasuke.
Itachi stands a better chance against Pein/Nagato than Sasuke, but Sasuke with EMS maybe able to defeat him, but we can only tell once we see what he is fully capable of.