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

With Alisson still out with a hamstring injury and Mamardashvili facing a spell on the sidelines, Woodman looks set to play against his boyhood club Crystal Palace at Anfield this weekend.

From BBC • Apr. 21, 2026

But sitting on the sidelines was too much of a risk, Goldman’s Blostein says.

From The Wall Street Journal • Apr. 9, 2026

Buffett was known for keeping enough cash on the sidelines that he could take advantage of opportunities as they arose, but he wouldn’t just shell out cash for just any name.

From Barron's • Apr. 8, 2026

Last April, retail investors in the U.S. stepped in to aggressively buy the post-“liberation day” dip in stocks while Wall Street professionals generally remained on the sidelines.

From MarketWatch • Apr. 6, 2026

I felt confident, especially when I caught sight of Martha on the sidelines, smiling broadly.

From "Courage to Soar" by Simone Biles