He started work at the sharp end of the business, as a salesman.

他从这一行最为棘手的工作做起，当了推销员。

《牛津词典》

That doesn't mean it can't feel like the exact opposite for some of those at the sharp end.

BBC: Bitter-sweet sympathy

My job at BABA is to ensure everything we do supports those at the sharp end: the boxers, their coaches and support teams.

BBC: New body to run GB Olympic boxing

Prof Smith has found himself at the sharp end of the slump - his department has been earmarked for closure by the university.

BBC: NEWS | UK | Magazine | What's the point of chemistry?