When they left for this mission, the pair was confident in their ability to track the guy down. After all, a serial killer had a pattern that they could follow, and with the number of murders that have been committed up to this point, there was no shortage of information to use. Sasuke's level-headedness had given them the edge they needed- and his tendency to structure a plan of attack gave them the jump on their target.

That didn't mean it went off without a hitch. Tracking the guy down was one thing, but this kishin was fast, and it was only due to quick thinking, Naruto's reflexes, and perfect resonation that the pair were able to avoid any critical damage. Though winded, Naruto and Sasuke managed to take their target down with injuries that were mostly superficial. It wasn't until they were on their way back that Sasuke pointed out their opponents seemed to be getting stronger.