Will the Real Oak Please Stand Up?

Ash, Brock, and Misty, on their adventure to the way to the Johto League, they stop to rest in a small town, and learn that Prof. Oak and Mary are doing an outdoor show in Maroon Town, a nearby town. They go there, and as usual, Team Rocket pop up and they impersonate Prof. Oak and Mary. A standoff to prove the real Prof. Oak is held, and the real Oak was, fortunately, picked, and Team Rocket get foiled.