Okay, I've never seen this guy as a staller/annoyer. I just thought of this from the top o' my head.

Ludicolo @ Shell Bell
(Rain Dish trait)
-Rain Dance
-Dive
-Leech Seed
-Fake Out

Start off with Rain Dance, recover HP from rain and shell bell, Leech Seed them, then keep diving. Fake out if you need to or as a finisher. After you've pulled it off, you'll be getting HP from Shell Bell, Leech Seed and the rain. After the rain fades, rain dance again. The reason he's an annoyer is you'll annoy your opponent.

NOTE: I don't know if it's really effective or not, since I have Ruby, not Sapphire.