The Last Leg: A Final Act of Desperation

is episode 106 of the original Naruto anime.

Synopsis
With Sakura Haruno and Sasuke Uchiha defeated, it is up to Naruto to defeat Aoi so Idate can continue the race. After a few failed attacks, Naruto is finally able to defeat Aoi, which means Idate can continue the race. Though Fukusuke is already near the finish line, with determination and encouragement from Naruto, Idate manages to catch up and win the race, seemingly saving the Wasabi family. However, the daimyō's minister objects, claiming that Idate cheated, as Naruto carried him for part of the race. According to the minister, this violates the rule that the runners must do the race on their own two legs. Just as it seems that Idate will be disqualified, the daimyō objects, declaring that no such rule exists. He then reveals a photo of the minister taking a bribe from the Wagarashi family, explaining why he had invented the rule. As a result of this, as well as other poor conduct, the Wagarashi are forcibly disbanded.