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

"Visually watching Mikel on the sidelines, it was elements of previous years where that energy reflected into the team," he said.

From BBC • Apr. 4, 2026

What’s more, retail investors now appear to be joining institutional players on the sidelines, he said, pointing to weekly fund flows.

From MarketWatch • Mar. 28, 2026

Few if any producers have committed to boost output yet, but if prices rise enough, it’s hard to imagine they sit on the sidelines for long.

From Barron's • Mar. 27, 2026

Tottenham Hotspur's Dominic Solanke is the other striker, making his way back this season after several months on the sidelines with an ankle problem.

From BBC • Mar. 20, 2026

Surprised, Peanut hesitated, then broke for his basket, not noticing that Ben trailed him and not noticing that a flight jacketed figure trailed Ben on the sidelines.

From "The Great Santini" by Pat Conroy