catch someone on the hop

catch someone on the hop

BRITISH
COMMON If a person or event catches you on the hop, you are not prepared for them and so are unable to respond quickly or appropriately. She couldn't afford to be caught on the hop if stock sold out. Adam took the fourth qualifying place in his semi-final and admitted his success had caught him on the hop. Compare with keep someone on the hop.
See also: catch, hop, on