Challenging a Towering Figure!
Ash and friends find out that the main event for the Twinleaf Town Festival is a battle tournament, and the winner gets to have a battle with the Sinnoh Battle Frontier Brain, Palmer. Excited about that, Ash enters the tournament with hopes of battling him.
Aired 03/09/2009EP 141 - Challenging a Towering Figure!

2006
Pokémon the Series: Diamond and Pearl
After defeating Brandon and declining the offer to be a Frontier Brain, Ash sets off to travel through the far away land of Sinnoh. Once he gets there, he meets up with Hikari, a local trainer from the region, and they decide to travel together.