I don't think the fight would happen at all, but if it did, naruto might stand a chance. Jiraiya said that kyubi chakra is mixing with naruto's, and I think that means it's becoming naruto's. Less chakra for kyubi. If, after a long while, kyubi finally gets released, he should be weaker than before. Naruto might be able to beat him then, not necessarily on his own, but still fight and defeat him. Specially if he actually becomes hokage. Would be good revenge for the 4th, stealing it's power then killing it.