I think Sasuke this is how I think the battle would go.

Naruto throws a couple of Kunai knives so Sasuke dodges them of course. Sasuke comes out of nowhere and then back attacks Sasuke. Eventually Naruto those a shadow clone jutsu and does Naruto Uzumaki Barrage. Afterwards Sasuke does a couple of Phoniex Flower jutsus and Fire style jutsu. Then while Naruto is off guard he does a Lions Barrage. So then Naruto turns into a Demon Naruto and Sasuke does Curse Mark Sasuke with Sharingon. So Naruto would charge up a Power Strike and Sasuke would do Chidori (Lightning Blade). But of course when they collide Sasuke has had more experience with his special while Naruto hasn't. So Naruto falls in defeat to make Sasuke the winner but barely.