Imagine the damage...

[Touken]

nagato was taken by surprise? he didn't see itachi attack nakara paths eyes? that should have tipped him off

did he not have a chameleon watching aswell?
yep he did

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Oh, so you've also forgotten Nagato wasn't in control? If Nagato was in control then that fight would have been a different story. Nagato would have utilized his sensing properly and wouldn't have been taken by surprise and would have also noticed that his summoning's eyes had been taken out.

 

[AGoodBoy]

the point is it would occupy preta giving sasuke time to kill nagato.

it wouldn't. Nagato absorbed V2 8 tails in seconds. He'd absorb this effortlessly. If sasuke tries to come closer, nagato simply uses ST; If that's not enough he uses asura limbs and missiles while ST cools down. Sasuke won't have time to get close on him.

Nagato > Sasuke/Naruto