Meaning of “if/when push comes to shove” - Learner’s Dictionary

if/when push comes to shove

informal

If you say that something can be done if push comes to shove, you mean that it can be done if the situation becomes so bad that you have to do it:

If push comes to shove, we'll just have to sell the car.

(Definition of “if/when push comes to shove” from the Cambridge Learner’s Dictionary © Cambridge University Press)