Park Warden

The park warden is a character of the day who appeared in One Trick Phony! (EP250). He is in charge of the Battle Park.

He brought Team Rocket, who was working at the battle facility, more boxes of dirty Poké Balls for cleaning and laughed off their disdain, saying he had the hard task of shopping and left Team Rocket in charge of the park while he went to get supplies.

Later, when Team Rocket flew off with the Poké Balls and Ash's Pikachu, the warden ran out telling them that the Poké Balls belong to the Battle Park. After Ash's Totodile and Misty's Politoed brought down their balloon, Jessie and James sent out Venusaur, Charizard, and Blastoise to battle Ash and his friends. However, the rental Pokémon turned on them, as they were only obedient inside the park and blasted the trio off.

(Source: Bulbapedia)