Nechrom
He only lose in a match not a battle, if it was real then Sasuke be dead. He doesn't even use a sword anymore for the past few year, so of course he gets rusty. And he just used 1 shadow arm if he bring it all out Sasuke be dead. Also it doesn't called master student relationship if Sasuke not even once defeated him. And like I said he is holding back not full power, I didn't even nerf him.