Definition of put someone on their mettle in US English:

put someone on their mettle


  • (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.’