I don't think this will be the end of Madara, I think that Naruto somehow stops Madara's plan and Obito dies, Sasuke may show up after the fight but then go with Madara. I wouldn't be surprised if Madara starts training Sasuke to use Perfect Susanoo and the Rinnegan. Then after the Sasuke and Naruto fight they team up to fight Madara when Sasuke has a change of heart or something along those lines.
not happening
I just don't think Sasuke and Naruto will team up until the end of the series, it will be the last fight or something. Sort of Sasuke's redemption.