There's a couple of people in here still referring to Ali as Cassius Clay or Mr. Clay. He's quite clear in this excellent interview talking about racism [1] tha

There's a couple of people in here still referring to Ali as Cassius Clay or Mr. Clay. He's quite clear in this excellent interview talking about racism [1] that Clay was a slave name and he was now a free man and wants to be called Muhammad Ali. > "How would a Chinese look named 'Robert Smith'?" [1]: https://www.youtube.com/watch?v=rtxfTEyJZg4