give someone a run for their money
give (one) a run for (one's) money
To challenge one's ability, fortitude, or patience. Don't underestimate our opponents today—I think they'll give us a run for our money. Having an infant and a toddler sure is giving me a run for my money.
give someone a run for their moneyINFORMAL
COMMON If you give a very skilful person or team a run for their money in a competition, you compete as well as them, or almost as well. The British team gave the host side a run for its money to finish a close second in the team competition. We think the Irish will give the Welsh a good run for their money.