Rob McElhenney, soon to be known as Rob Mac, is defending the decision to change his last name. In a recent post on X, McElhenney shared a brief video explaining why he abridged his last name for those still scratching their heads over the news.

Rob McElhenney has filed legal documents to change his name. The actor reportedly signed the docs Thursday requesting that his surname be changed to Mac — so his new name will be Rob Mac, according to multiple outlets.

Call him an actor, writer, producer, director, Welsh soccer-team owner and creator of "It's Always Sunny in Philadelphia" – just don't call him Rob McElhenney.