weak link

Idioms  

1. The least dependable member of a group, as in The shipping department, slow in getting out orders, is our weak link in customer service, or They're all very capable designers except for Ron, who is clearly the weak link. This expression alludes to the fragile portion of a chain, where it is most likely to break. [Mid-1800s]

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Example Sentences

The secondary is the weak link in the Rams defense and he’s absolutely a broken link.

From Los Angeles Times

Her production of “Ragtime,” with its sumptuous score by Stephen Flaherty and Lynn Ahrens, had nary a weak link in a cast of characters among the most expansive in the recent annals of musicals.

From The Wall Street Journal

Thus, Roberts had to look elsewhere among a relief corps that had been the weak link of the team all season.

From Los Angeles Times

They are just looking for a weak link, he tells Panorama.

From BBC

Culkin, the weak link in the otherwise sturdy “Glengarry” revival, was passed over for a featured actor nomination.

From Los Angeles Times