Pokemon Best Wishes! - episode 55 - 09 Nov, 2011

While on their way to Driftveil City, Ash and co. encounter a young girl named Katharine, and her Pokémon, Gothita, who has taken a liking to Ash's Scraggy due to its staring. Katharine challenges Ash to a battle, to which if she wins, he must trade his Scraggy for her Gothita. (Source: Wikipedia)