on the sidelines

Idioms  

1. Observing rather than taking part, out of the action, as in Bolivia's neighbors remained on the sidelines, waiting to see which faction in the dispute would prevail. This idiom comes from sports. The sidelines are the two lines defining the sides of the court or playing field and the area immediately beyond them where, in such sports as football, the non-playing team members sit. [First half of 1900s]

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Example Sentences

The rule applies to players, coaches and officials on the sidelines during matches.

From Los Angeles Times • Jun. 8, 2026

While for now he will sit on the sidelines, Damodaran said he would reconsider if the stock drops enough.

From MarketWatch • Jun. 5, 2026

GM, Ford and Toyota have said they are planning for new-car sales to stagnate or shrink this year, as prospective buyers stay on the sidelines of the market.

From The Wall Street Journal • May 28, 2026

Others, like Italy, argue that it's unwise to stay on the sidelines any longer.

From BBC • May 26, 2026

Until he was ten, Bobby’s regimen was fairly routine: He played at the Brooklyn Chess Club every Friday night, with Regina sitting on the sidelines, reading a book or doing her nursing homework.

From "Endgame" by Frank Brady