Definition of knock someone off their perch in US English:

knock someone off their perch

phrase

informal
  • Cause someone to lose a position of superiority or preeminence.

    ‘will this knock London off its perch as Europe's leading financial center?’
    • ‘They believe they can knock Australia off their perch and become the dominant team in world one-day cricket, the coach said here in New Zealand yesterday.’
    • ‘But, he knows that it will may take something special to knock them off their perch.’
    • ‘Can anyone really see a midfield knocking them off their perch?’
    • ‘The inspectors are irritated because it knocked them off their perch, undermining their authority and purpose on the world stage.’
    • ‘But first things first and we will go out with every intention of trying to knock them off their perch.’
    • ‘We'll be trying to knock them off their perch next year, but then again, that's what it's all about!’
    • ‘There is no point in being over ambitious and aiming for to knock Kerry off their perch.’
    • ‘The high-flying Tykes had run up a record seven successive victories in the tournament before Durham knocked them off their perch last year.’
    • ‘Alex didn't knock them off their perch, he has buried them!’
    • ‘They are still the deepest team in the East, and knocking them off their perch won't be easy.’