{adv. phr.} In a trap, with no way to escape; in bad trouble. * /The soldiers had their backs to the wall./ * /He was in debt and could not get any help; his back was against the wall./ * /The team had their backs to the wall in the second half./ Compare: BETWEEN THE DEVIL AND THE DEEP BLUE SEA, LAST DITCH, ON THE SPOT, UP AGAINST IT.
BACK AGAINST THE WALL
Meaning of BACK AGAINST THE WALL in English
Slang English vocab. Английский сленговый словарь. 2012