@hightor,
Muhammad Ali comes to mind. He was, by God, the GREATEST in his own mind (and that of many others) and he would freely tell you so.
If you didn't like it, or thought otherwise, then come step into the ring with him.
It aint braggin if you can back it up.
No champion, at anything, ever existed who didn't think he was, or at least could be, the BEST.