Byrd's first pro fight was at light heavyweight in 1993 and his 4th fight in 1994 was at heavyweight. He fought Vitali in 2000.
Gennady Golovkin won Gold at light welterweight in the amateurs, but nobody calls him a "blown up light welterweight". Tomasz Adamek fought at welterweight in the amateurs. Even Wladimir Klitschko was in the "under 200" category for most of his amateur fights.
Billy Conn, considered one of Joe Louis' best wins, had his first pro fight at lightweight (135).
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