Question: Which Canadian sports announcer started his career at 16 and now does the play-by-play on "Showtime Championship Boxing"?
Sentence (from "Mauro Ranallo"): He is currently signed as a play-by-play announcer with MMA organization Bellator, professional wrestling promotion WWE (on their NXT brand) and also performs play-by-play duties for boxing broadcaster Showtime, most notably, the Floyd Mayweather Jr. vs. Conor McGregor bout.
Relevant evidence: No