He’s remained humble in recent years, but there was a time when Sasuke had to accept that Naruto exceeded him in strength. But when does Sasuke realize Naruto is stronger?
Sasuke is able to realize that Naruto is stronger during their rooftop battle. Naruto’s Rasengan completely explodes the backside of a water tower while Sasuke’s Chidori barely made damage by comparison. At this moment, Sasuke realized Naruto’s growth exceeded his own.
Their fight follows a growing insecurity within Sasuke. He was already agitated after Naruto saved the day against Gaara earlier.
Plot Behind How Sasuke Realizes Naruto is Stronger
Starting in chapter #173, Sasuke wakes up in the hospital after his fight with Gaara. He has a flashback of admitting that Naruto was the one who rescued Sakura, fighting desperately and “showing a strength never seen before.”
Sasuke feels anger over Naruto narrowing the gap. He thinks of Naruto’s clone jutsu and toad summoning. Sakura offers Sasuke apple slices, but he slaps the tray away, staring off into thought as the following panel matches the glare of Orochimaru.
Naruto enters the room to visit Sasuke. He has more flashbacks of Jiraiya saying that capturing Naruto is the true goal of the Akatsuki, as well as Itachi stating that he has no interest in Sasuke. He challenges Naruto to a fight and the two head for the roof.
The two build up their strongest jutsu: Chidori and Rasengan. Before the powerful jutsu are able to collide, Kakashi interrupts the fight and directs the boys’ attacks off course. Both of their attacks land into two different water towers on opposite sides of the rooftop, trapping their hands inside.
Sasuke pulls his post-Chidori hand out of the water tower. He is feeling proud of himself over the large amount of damage he created. Kakashi even questions if Sasuke meant to kill Naruto with the size of the attack.
He jumps down, seeing the backside of the water tower that Naruto collided into. The backside is absolutely obliterated by the Rasengan. All the water has been removed from the tower and the entire inside is exposed.
Sasuke stares in astonishment and begrudgingly asks himself how Naruto could improve so fast.
Here’s the answer: Sasuke is able to realize that Naruto is stronger when the Rasengan does more damage to a water tower than his Chidori was able to.