To whoever is reading this: The Yahoo! Sports writer is confused about the use of whomever (which is the objective case of whoever and is used as the object of a preposition) and whoever (which can be the subject of a verb like was listening):
This writer isn’t alone in his confusion. To many people, it appears that whomever is the object of the preposition to, but it’s the entire clause that’s the object of the preposition. And whoever should be the subject of the verb in that clause.
If you’re not into being grammatically nitpicky and you’re faced with the choice between who and whom or whoever and whomever, go with who or whoever. In more the half the cases, you’ll be correct, and even if you’re wrong, your writing will sound more authentic and less stilted and formal.