Pokemon Best Wishes! - episode 15 - 05 Jan, 2011

After being given a short tour of the Nacrene City Museum, Lenora accepts Ash's challenge. Lenora eventually defeats Ash, who feels dejected until Don George tells him not to give up so easily, promising to teach Ash's Pokémon a new move. Meanwhile, Team Rocket infiltrates the museum and steals the meteorite, replacing it with the fake one they received earlier. (Source: Wikipedia)