Pierce O’Leary is defeated for the first time in his professional career by Mark Chamberlain in a fight at Dublin’s 3Arena. All reports describe a close, competitive contest in which Chamberlain ultimately prevents O’Leary from coming out victorious. The bout is reported as ending with O’Leary being stopped in the later stages, with one account specifying the stoppage occurs in the tenth round. The Irish fighter is described as being stopped by the English opponent in a “thriller” and a “cracking contest,” with coverage emphasizing that the fight reaches an extended, high-intensity period rather than ending early. Sports outlets also align on the key outcome: Chamberlain records the win and O’Leary takes his first professional loss. The reports do not add differing details on the setting beyond the venue being 3Arena in Dublin, and they largely agree on the identity of the fighters, the event location, and the decisive stoppage leading to O’Leary’s first defeat.