Barry's Busting Out All Over! - S11.E49

Upon arriving at the Hearthome Gym, Ash and his friends run into Barry, a trainer from Twinleaf Town. Barry turns out to be an admirer of Paul, whom he saw when watching the Double Battle Tournament. Ash challenges Barry to a Pokémon battle. Ash chooses Chimchar, Gliscor, and Pikachu, against Barry's Staraptor, Roserade, and Empoleon. Ash manages to narrowly defeat Barry, finishing off Empoleon with Pikachu's Volt Tackle.