step into the breach

US /stɛp ˈɪntu ðə briːtʃ/
UK /stɛp ˈɪntu ðə briːtʃ/
"step into the breach" picture
1.

einspringen, die Lücke füllen

to take action when another person or group is unable to, or to fill a gap in a difficult situation

:
When the lead actor fell ill, his understudy had to step into the breach.
Als der Hauptdarsteller erkrankte, musste sein Ersatz einspringen.
The volunteers had to step into the breach when the regular staff went on strike.
Die Freiwilligen mussten einspringen, als das Stammpersonal streikte.