4th wins, hands down
Itachi can't even see him, How is he going to beat him??
First, Someone said he is master of sharingan so I don't think Itachi's sharingan can predict more than any other's When Raikage has more speed than sharingan then 4th really will be a nightmare for Itachi.
Second, When Itachi can't see 4th how he is going to land any of his attacks on him, after some time Itachi ll' start losing his stamina and 4th ll' easily dispose him off.
Third, If by any twist of luck he is able to predict him, even then he can't win coz we all know 4th was the god of sealing techs in konoha and he doesn't only use rasengan and FTG, he is also good at diversion techs and we don't know much about him so saying that Itachi is the genius of Uchiha doesn't win the fight for him, 4th is said to be the ninja who borns in 100 years.
Fourth, If some of you contradict on my statement that we still don't know what Itachi is capable of, too will just have a big mouth. Itachi's limits are shown in series, even if he's going to use it against 4th at his full. 4th is still a hell out of a ninja who is considered such a powerful with just his rasengan and FTG, if he's to show his limits no ninja in the world can beat him (ex. So6P). Someone said here that the reason why 4th has to die is simple as he said that there would be no akatsuki left to deal with in ninja world and for the assault on uchiha instead of itachi, 4th would have been selected........
I m just not saying Itachi is a goner but to compare him to the finest shinobi we have seen so far (ex. So6P) is just ridiculous.