Vince is confusing the first one with the 2nd. The so-called "phantom punch" was in the 2nd fight. Rabbi-Sol has it right.
Ali was not a lights-out puncher in the mold of Foreman, liston, etc, but he could punch pretty well. Take a look at the films of his knockout of Cleveland Wiliams, for one, and his knockout of Zora Folley for another, just to name two.