The Ultimate Battle: Cha!

is episode 42 of the original Naruto anime.

Synopsis
Sakura and Ino's battle rages on. With both nearly out of chakra, Ino tries a desperate move: her Mind Body Switch Technique. She succeeds and takes control over Sakura's body. As she prepares to force Sakura to forfeit, Naruto cheers Sakura on and inadvertently awakens Inner Sakura, who forces Ino out of her body. Both drained of their chakra, the rivals knock each other out in one climactic punch, resulting in a double knockout. Neither candidate advances to the final stage.