World middleweight title claim · 20 rounds

Jack
Twin Sullivan
VS
Philadelphia
Jack O'Brien

O'Brien · KO 3/20

Apr 14, 1904 · West End A.C., Saint Louis, 🇺🇸

Sullivan going in0-2-0

O'Brien going in113-6-18

Confirmation✓ one source

MethodKO

Round3 of 20

TitleWorld middleweight title claim

Sources

English Wikipedia
side b · observed 2026-10-11
en.wikipedia.org/wiki/Philadelphia_Jack_O'Brien

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