Definition of put someone on their mettle in English:

put someone on their mettle

phrase

  • (of a demanding situation) test someone's ability to face difficulties.

    ‘This way of thinking was made explicit only when critics such as Vincenzo Borghini were put on their mettle to defend the Baptistery's antiquity.’
    ‘Coventry's opening was brisk and sufficiently to the point to put Tottenham on their mettle.’