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

“I won’t sit on the sidelines,” he said.

From The Wall Street Journal

For Liverpool, who have seemingly turned a corner and are now unbeaten in six, the problems continue to mount though with Isak and Conor Bradley both facing a spell on the sidelines.

From BBC

The president approved the Navy’s plan for “Golden Fleet” in a Dec. 3 Oval Office meeting with Defense Secretary Pete Hegseth, Phelan and Russell Vought, the director of the Office of Management and Budget, Phelan told The Wall Street Journal on the sidelines of the Reagan National Defense Forum earlier this month.

From The Wall Street Journal

The low rate of unretirement today suggests that older workers are finding it difficult to re-enter the labor market and thus staying on the sidelines.

From MarketWatch

“It is of enormous importance that we get the green light for Mercosur and that we can complete the signatures for Mercosur,” she said on the sidelines of a key meeting of EU leaders in Brussels on Thursday.

From The Wall Street Journal