(put/catch somebody) on the back foot verb phrase
To put somebody in a difficult or disadvantageous situation
The Covid-19 outbreak has put the national economy on the back foot.
The unexpected problem caught me on the wrong foot.
The verb "put" and "catch" should be conjugated according to their tense.
"on the back foot" is a phrase that is most probably derived from the sport of cricket. A stance where most of the player’s weight is on the back foot refers to a situation in which he is delivering a defensive stroke.
Used to allude that the last force, problem or burden which is seemingly minor and small causes a person, system or organisation to collapse or fail
Her husband's violent act last night was the straw that broke the donkey's back and she left him