like one's life depended on it
Definition from Wiktionary, the free dictionary
- (idiomatic) desperately
2011 January 5, Jonathan Stevenson, “Arsenal 0 - 0 Man City”, BBC:
- With Carlos Tevez chasing down every lost cause like his life depended on it, City always had an out ball but Arsenal had such a monopoly on possession that they barely had to give thought even to the Argentine.