Упавшего не считай за пропавшего

Even a loser has a chance. See Не всякая болезнь к смерти (H)

Cf: All is not lost that is in danger (Am.). All is not lost that is in peril (Br.). Не that falls today may rise tomorrow (Br.). A man may be down, but he's never out (Am.). Near dead never filled the kirkyard (Am.). No man is dead till he's dead (Am.)