noun
underdog
Borrowed from English; used in sports, competition, or social contexts to refer to a person or team expected to lose.
彼はいつもアンダードッグを応援する。
He always roots for the underdog.
その試合でアンダードッグが勝った。
The underdog won that match.
A more general Japanese term for a weak person or the weak; アンダードッグ specifically implies a competitor expected to lose.
Loanword from English 'underdog'.