Question: What nationality is the boxer who went against Sean Mannion or the vacant WBA title and won over a fifteen round unanimous decision?
Sentence (from "Mike McCallum"): He is a three-weight world champion, having held the WBA super welterweight title from 1984 to 1988; the WBA middleweight title from 1989 to 1991; and the WBC light heavyweight title from 1994 to 1995.
Relevant evidence: No