What is a good Pyschic pokemon for pearl?

I've lost from her many times too, but the last time I was using Wind Pokemons, or more precisely, a pokemon that has the "Fly" ability. I myself used Swellow (the sparrow like pokemon what's it's name). So you need to use just 1 fighting type pokemon to evaluate her strenght and damage, and then use a wind type pokemon, so you fly up in the air to evade her attacks with the "Fly" ability, and then easily beat her.