12 rounds

Jack
"Twin" Sullivan
VS
Frank
Klaus

Klaus · PTS 12/12

Jan 18, 1910 · Armory A.A., Boston, 🇺🇸

Sullivan going in—

Klaus going in40-9-10

Confirmation✓ one source

MethodPTS

Round12 of 12

Sources

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

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