the odds are stacked against you

US /ðə ɑːdz ɑː stækt əˈɡɛnst ju/
UK /ðə ɑːdz ɑː stækt əˈɡɛnst ju/
"the odds are stacked against you" picture
1.

as chances estão contra você, as probabilidades são desfavoráveis

the chances of you succeeding are very small

:
He knows the odds are stacked against him, but he's still going to try.
Ele sabe que as chances estão contra ele, mas ainda assim vai tentar.
With so many experienced competitors, the odds are stacked against you.
Com tantos concorrentes experientes, as chances estão contra você.