Rudy put all his efforts into wooing Misty after she saved his younger sister, Mahri, from a whirlpool, instead of focusing on Ash's challenge. Like most members of the Orange Crew, Rudy requires that all Trainers who face him pass a test of skill. He had Ash's Pokémon shoot at targets while aboard a moving boat.

After Ash passed Rudy's attack test, he faced him in a three-on-three battle pitting Pokémon of the same type against each other atop one of the rock pillars that surrounds Trovita Island. Prior to the fight, Rudy asked Misty if she wanted to stay with him after the match, but permitted Misty to decide after the battle was over. Ash lost the first round of the battle — Pikachu versus Electabuzz — but Bulbasaur won the battle against an Exeggutor by using Sleep Powder on it, causing it to fall off the pillar before Bulbasaur caught it with Vine Whip.

When the final round came — Squirtle versus Starmie — Rudy dedicated the fight to Misty, subsequently ordering Starmie — evading Squirtle's Water Gun by dancing — to spin itself into a Thunderbolt. As Ash tried to think of a strategy, Misty, finally making up her mind, yelled at Ash to keep fighting as he was the only one who could bring out Squirtle's real power. His resolve renewed, Ash had Squirtle use Water Gun to force itself out of the path of Rudy's Thunderbolt, Squirtle subsequently learning Hydro Pump just in time to stop it falling into the nearby sea, subsequently using Hydro Pump and Skull Bash to defeat Starmie. After presenting Ash with his badge and Misty with some flowers as a farewell, Rudy commented that he hoped Ash knew that he was a very lucky guy, and that Ash would find out what he meant some day.