Naruto was able to fight because she was there. Wikipedia
Sakura Haruno (春野 サクラHaruno Sakura?) is a fictional character in the Narutomanga and anime series created by Masashi Kishimoto. In the anime and manga, Sakura is a kunoichi affiliated with the village of the Hidden Leaf (Konohagakure), and apart of Team 7, which consists of herself, Naruto Uzumaki, Sasuke Uchiha, and their senseiKakashi Hatake. Sakura initially has an infatuation for Sasuke, praising him at every juncture, and heaped scorn upon the less skilled teammate Naruto. Over the course of the series, she begins to shed this singularly driven persona, and grows more appreciative and accepting of Naruto. Sakura has appeared in several pieces of Naruto media, including nine featured films in the series, all the original video animations, and several video games.
Sakura has become the series' female lead, although, she was not immediately intended for the role. Kishimoto has had difficulty drawing her character resulting in Kishimoto inadvertently emphasizing certain parts of her appearance, including her large forehead. Chie Nakamura voices the character in the animated adaptations of the series, while Kate Higgins plays her in the English dub.
Numerous anime and manga publications have praised and criticized Sakura's character. She was initially noted to be a stereotypical shōnen character, serving as a love interest for the protagonist, and served little purpose in the series initially beyond being comic relief.[3][4] Her emergence from this stereotype as the series progressed has been celebrated by many reviewers.[5] Amongst the Naruto reader base, Sakura has been popular, placing high in some polls. Several pieces of merchandise have been released in Sakura's likeness, such as a plush doll and key chains.